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THE AMERICAN GEOGRAPHICAL SOCIETY OF NEW YORK 

GUIDEBOOK 

FOR THE 
TRANSCONTINENTAL EXCURSION 

OF 1912 



WITH THE COMPLIMENTS OF 

GINN AND COMPANY, PUBLISHERS 



■X)ZL 



£:CI.A8J!N76 



PREFACE 

The attempt is made in the following pages to present a 
concise explanatory account of the larger physiographic prov- 
inces of the United States which are to be traversed by the 
Transcontinental Excursion of 1912, and a more detailed state- 
ment of the local features seen along the route of the Excur- 
sion in their relation to the provinces in which they belong. 
The treatment of different parts of our route is unavoidably 
uneven, partly from lack of material, but more from lack of 
time available for the work of compilation. If greater em- 
phasis is given to physiographic than to ontographic factors, 
this is not due to any want of respect for the importance of the 
second, but simply to the much greater abundance of published 
material regarding the first. 

A number of the speciahsts whose studies are here cited or 
who have directly contributed to the preparation of this guide- 
book will be members of the Excursion for longer or shorter 
periods. Many details, necessarily omitted here, will be pre- 
sented orally on the ground by experts well qualified to speak 
upon them. 

W. M. D. 



Cran)Scontincntal €xtnv^ion of 1912 

PART I. THE PHYSIOGRAPHIC PROVINCES 
OF THE UNITED STATES 

THE EASTERN UNITED STATES 

The Four Belts of the Eastern United States. — The eastern 
part of the United States may be divided into four physiographic 
belts, trending northeast-southwest, i. The Atlantic coastal 
plain, bordering the sea and consisting for the most part of im- 
perfectly consolidated strata dipping gently southeast, partly 
stripped from their original inland extension and more or less 
elaborately dissected. The plain has, in consequence of a 
modern depression, been invaded by the sea along its northern 
part, and thus reduced in breadth or completely submerged. 
2. The older or crystalline Appalachian belt, consisting of greatly 
disordered crystalhne rocks, usually appearing as an uplifted 
peneplain surmounted by subdued monadnocks and maturely 
dissected by numerous valleys; this belt served as the oldland 
to the Atlantic coastal plain. 3. The newer Or folded Appa- 
lachian belt, consisting of a heavy series of stratified formations 
of varying resistance and of folded structure, which like the 
crystalline belt has been at least once reduced to old age since 
the folding, and which now, after renewed regional elevation, 
presents the resistant strata in long, even-crested ridges, while 
the weaker strata are reduced to subsequent lowlands with well- 
adjusted drainage. 4. The Appalachian plateau, consisting of 



2 THE EASTERN UNITED STATES 

the same stratified formations as the folded belt, but here lying 
nearly horizontal and elaborately dissected by insequent streams. 
The plateau gradually descends to the northwest and passes into 
the drift-covered prairie plains of the upper Mississippi basin. 

The four belts vary greatly along their length. Each one may 
now be reviewed in more detail. 

The Atlantic Coastal Plain. — The inner part of the Atlantic 
coastal plain appears to have passed through one cycle of 








im 



^M 



Fig. I. A Branch of Chesapeake Bay, in the Atlantic Coastal Plain. 

erosion, and then, after renewed uplift whereby it was extended 
seaward, to have reached maturity in a second cycle. Still 
later it lost a large part of its former extension to the northeast 
by submergence ; it now ends at New York harbor — except 
for drift-covered remnants of a cuesta visible in Long island 
and other islands farther eastward — so that the ocean reaches 
and overlaps the gently descending upland or inclined peneplain 
of the crystalline belt along the New England coast. Various 
plants, common to the coast of Nova Scotia and the middle 
Atlantic States, are supposed by Fernald to have reached their 
northeastern habitat before the coastal plain was lost by sub- 



THE OLDER APPALACHIAN BELT 3 

mergence along the New England coast. Southwest of New 
York harbor, from New Jersey to North Carolina, the coastal 
plain widens ; its border is here interrupted by many elaborately 
branching embayments that result from the slight submergence 
of its previously eroded valleys. Some of the long, narrow dig- 
itate bays bring tidewater all across the coastal plain to the 
border of the crystalline belt, as will be seen in the Potomac 
river (or more properly, estuary) at Washington. In New 
Jersey the coastal plain is longitudinally belted ; a broad cuesta 
of small relief incloses an inner lowland, which offers a low-grade 
pathway from New York city southwestward to Philadelphia. 
In South Carolina and Georgia the coastal plain has a maximum 
breadth of 120 miles and is not embayed; its seaward margin 
is there a low, young, featureless plain, beneath which the valleys 
of even the largest rivers are very slightly incised. 

The Older Appalachian Belt. — The greater part of the older 
Appalachian belt may, as already stated, be best described as 
an uplifted peneplain, surmounted by subdued monadnocks, 
irregularly placed, singly or in groups ; the peneplain is maturely 
dissected ; occasional areas of weaker rocks are reduced to local 
peneplains of a later generation. The outer or southeastern 
border of the belt is determined by the retreating overlap of 
the coastal plain strata ; the inner or northwestern border, by 
the sudden down-bending of the crystalline rocks under the heavy 
strata of the folded belt. The breadth of the crystalline belt 
is greatest in New England, where in spite of the depression by 
which some of its outer border is submerged, it measures from 
130 to 180 miles from southeast to northwest ; its inner (north- 
western) part reaches altitudes of 1000 or 1600 feet, and is so 
greatly diversified by surviving monadnocks and incised valleys 
that the supposed uphfted peneplain is frequently not to be 
recognized. A great breadth of 170 or 180 miles is again attained 



4 THE EASTERN UNITED STATES 

in North Carolina, where the inner part of the belt is as much 
diversified as in New England. The difference in local aspect 
of these two broadest parts of the older Appalachians is largely 
due to the glaciation of the New England area, and is particularly 
apparent in the valleys: in North Carolina the drainage is 
typical of normally developed, mature rivers and valleys ; in 
New England small lakes, usually held by drift barriers, are very 
numerous, and waterfalls abound as the result of local super- 
position of streams on ledges. 

Interruption of the Older Appalachians. — The middle stretch 
of the older Appalachians, especially between New York and 
Philadelphia, is narrow, low, and interrupted. It is narrow, 
because of an inward bend of the over apping coastal plain 
border, so that the breadth of the crystalline belt is reduced to 
50 miles or less. Even this small breadth was once still smaller, 
for the overlapping coastal plain strata have been worn off 
from their original inland extension, stripping a formerly covered 
part of the crystalhne peneplain ; the stripped belt is frequently 
traversed by superimposed streams in narrow gorges, excellent 
e:^amples of which occur near Philadelphia. The middle stretch 
is low, seldom exceeding 600 or 800 feet even along its inner 
border, because its uplift was moderate. Hence the older Appa- 
lachian belt does not here constitute a formidable barrier between 
the coast and the interior, as is the case in New England and 
North Carolina. Finally, the upland of the middle stretch is 
interrupted, for it frequently includes infolded or down-faulted 
areas of weaker rocks, which are now worn down to lowlands 
beneath the upHfted peneplain of the inclosing crystallines. 

Notable among these areas of included weaker rocks are certain 
limestones and shales in southeastern Pennsylvania, where the 
resultant lowlands are famous for their fertility ; and more im- 
portant in extent are the red shales and sandstones of north- 



THE FOUR PRONGS OF THE OLDER APPALACHIANS 5 

westward dip, which occupy a long gently curving strip that 
extends from north of New York city across northern New Jersey, 
Pennsylvania, and Maryland into Virginia. This strip is highly 
significant, in that it obliquely traverses the middle stretch of 
the older Appalachian belt, where it is narrowest and lowest, 
so that the crystalline uplands are here partly replaced by low- 
lands for 300 miles. There are occasional tilted trap sheets 
contained in the red shale and sandstone series, and these survive 
in long, narrow, even-crested, monoclinal ridges, of which the 
Pahsades, across the Hudson from New York city, constitute 
a fine example. Other trap ridges are crossed in a local excur- 
sion from New York into Pennsylvania. But the trap ridges 
are local and discontinuous ; the older crystalhne belt is so 
largely interrupted all through its low and narrow middle stretch, 
that instead of forming a highland barrier, the lowlands by which 
it is replaced serve as gateways to the interior. 

The Four Prongs of the Older Appalachians. — The path of 
the included red-sandstone strip in the older Appalachian belt 
deserves particular attention. If one follows the highlands of 
the crystalline rocks southwestward from their broad expanse 
in New England to their narrower middle stretch, they are seen 
to be divided at Peekskill on the Hudson into two prongs by 
the northeastern point of the weaker sandstone strip ; a shorter 
and low prong on the southeast, which may be called the Man- 
hattan prong because the greater part of New York city, origi- 
nally called Manhattan, hes upon its extremity; and a longer 
and higher prong on the northwest, which may be named after 
the city of Reading, which hes just below its end in east- 
central Pennsylvania. Similarly, if the broad and mountainous 
highlands of North Carolina are followed northeastward, they 
are divided into two prongs by the long southern end of the sand- 
stone strip; a long and low prong in the southeast, extending 



6 THE EASTERN UNITED STATES 

past Philadelphia to Trenton ; and a shorter and higher prong 
on the northwest, which terminates near Cumberland in south- 
central Pennsylvania. These four prongs, the Manhattan and 
the Reading on the northeast, and the Trenton and the Cum- 
berland on the southwest, serve as convenient points of reference 
in various local descriptions. Between them, the lowlands of 
the sandstone strip occupy the whole space between the coastal 
plain on the exterior side and the lowlands of the folded Appa- 
lachians on the interior. 

The folded Appalachian belt possesses, especially in Penn- 
svlvania and Virs^inia, several resistant sandstones, which now 




Fig. 2. Diagram of the Allegheny Mountains. 

stand up with a relief of from 500 to 2000 feet in long, narrow, 
even-crested ridges, to which the general name Allegheny moun- 
tains is sometimes applied ; they follow sharply zigzag patterns 
in consequence of the gentle pitch given to the anticlinal and 
synchnal axes at the time of folding. The ridges are here and 
there cut down in water gaps by transverse streams, which connect 



THE FOLDED APPALACHIAN BELT 7 

the longitudinal valley lowlands eroded along the belts of weaker 
strata by revived subsequent streams. Far to the southwest, 
in Tennessee, northwestern Georgia, and northeastern Alabama, 
the resistant sandstones of the folded belt are thinner and the 
ridges are less conspicuous, as we shall see on our return route ; 
they are there frequently notched, so as to form lines of detached 
hills, known as " comby ridges." In the northeast, the folded 
belt narrows and is partly replaced by the plateau belt which 
advances from the west in northeastern Pennsylvania. It is 
in the synclines of the Pennsylvania section that anthracite 
coal occurs : the local excursion into Pennsylvania before our 
departure from New York, gives a view of parts of the district 
where the eastward advance of the plateau replaces the folded 
belt. Farther to the northeast, in eastern New York, the ridge- 
making strata disappear, so that the folded belt is there repre- 
sented by a lowland known as the Hudson valley, in its breadth 
of some 30 miles from the high inner border of the older Appa- 
lachian highlands to the escarpment of the Appalachian plateau, 
here known as the Catskill mountains. The plateau ends there. 
Still farther north, the crystalline mass of the Adirondack moun- 
tains replaces the plateau ; here the lowlands of the folded Appa- 
lachian belt are in large part submerged in the basin of Lake 
Champlain, which drains northward to the St. Lawrence ; and 
the valley of the St. Lawrence, trending northeastward between 
the highlands of New England and the Laurentian highlands 
of Canada, may be regarded as a distant extension of the folded 
Appalachians. Through the whole extent of the folded belt 
a moderate regional uplift has caused the streams to incise new 
valleys, usually mature, beneath the lowlands of the previous 
cycle, which therefore now deserve to be described as low uplands. 
This will be apparent as we ascend the Hudson to Albany on 
the first day of the Excursion. 



8 



THE EASTERN UNITED STATES 



The Appalachian plateau, now in the maturity of the current 
cycle of erosion, after having reached a more advanced stage in 
a previous cycle, is a region of elaborately dissected hills and | 
spurs which branch into a labyrinth of insequent valleys, with 
maximum local rehef of looo or more feet. The plateau belt 
is rather sharply defined along its eastern border by the abrupt 
change from its nearly horizontal structure to the strongly up- 
folded structure of the adjoining 
belt. The eastward advance of the 
plateau border, where the folded belt 
narrows in northeastern Pennsyl- 
vania, and the end of the plateau 
belt in the Catskills have already 
been mentioned. The plateau and 
the two other Appalachian belts 
gradually descend southwestward 
and disappear under the coastal 
plain of the Gulf States in north- 
central Alabama. The westward 
descent of the plateau to the prairies 
is usually gradual ; but it is accom- 
phshed in two dissected escarpments 
in central Kentucky, on account of 
the occurrence there of two lime- 
stones beneath scarp-making sandstones. To the northeast 
the plateau has a much less extension than the other two 
belts, because its strata gradually rise on approaching the 
uplifted mass of the Adirondacks — the group of subdued 
mountains in northeastern New York — and as the lower 
members of the plateau series are relatively weak, they are 
now worn down in a west-east subsequent valley, the 
Mohawk valley, into which we turn westward from the 




^L. . 

GULF OF M E XI C 0^'^ [^ 



Fig. 3. The Coastal Plain of 
Alabama. 



DRAINAGE OF THE APPALACHIAN BELTS 9 

north-south Hudson valley at Albany on our first day out 
from Xew A'ork. 

Drainage of the Appalachian Belts. — The folded Appalachians 
are accompanied through their whole length of over 1000 miles 
by a lowland, which sometimes occupies only their southeastern 
border, as in Mrginia and Pennsylvania ; sometimes their entire 
breadth, as in eastern Xew York. This long-continued lowland 
is often called the Great Appalachian valley. Its different parts 
are commonly known under dift'erent names. We follow the 
part known as the Hudson valley from Fishkill to Albany on 
our first day's run ; we cross the part known as the Valley of 
East Tennessee after leaving Chattanooga near the end of our 
return journey. 

The Great Appalachian valley is not a simple valley in the 
sense of being followed by a single river. It is a lowland of 
erosion that is composed of many broadly opened, head-to-head, 
confluent, longitudinal valleys, most of which are drained by 
the subsequent branches of transverse rivers. Some of these 
rivers deserve special mention. 

Four rivers in the middle stretch of the Appalachians, the 
Hudson, Delaware, Susquehanna, and Potomac, rise in the 
Appalachian plateau and traverse the two other Appalachian 
belts and the coastal plain on their southeastward course to the 
Atlantic. A fifth, the James, rises in the central part of the 
Great Appalachian valley and traverses the crystalhne belt and 
the coastal plain. To the northeast in Xew England and to the 
southwest in Xorth Carolina, the broad and high areas of the 
older Appalachian belt are not traversed by any river ; all 
Atlantic rivers head in the uplands and highlands of those two 
mountainous districts. In the north, the inner part of the high- 
lands and the adjacent part of the Great Appalachian valley 
are drained northwestward, to the St. Lawrence ; and in the 



lo THE EASTERN UNITED STATES 

southwest, by the Kanawha and Tennessee westward through the 
Appalachian plateau to the Mississippi — as we shall see at 
Chattanooga — and by the Coosa southward across the over- 
lapping coastal j^lain to the Gulf of Mexico. 

Settlement and Boundaries. — The embayments of the Atlantic 
coast line, formed by the submergence of lowlands or valleys, 




Fig. 4. Canyon of the Kanawha l\.i\ cr in the Allegheny Plateau, 
West Virginia. 

determined the location of nearly all the original colonies in the 
seventeenth century; and with respect to these as centers of 
influence the boundaries separating them were deiined. The 
generally north-southward trend of the coast line resulted in 
establishing east-west boundaries in many cases ; but the east- 
west trend of the coast of southern New England determined 
the north-south boundaries between Rhode Island and Con- 
necticut, and between Connecticut and New York; again, the 
northeast-southwest trend of the south Atlantic coast produced 
the northwest-southeast boundaries between North and South 
Carolina, and between South Carolina and Georgia. 

The entrance of some colonies into elongated embayments, 



SETTLEMENT AND BOUNDARIES ii 

trending southward, cut off the westward extension of the 
colony next to the east : thus Pennsylvania, first settled at 
Philadelphia on the estuary of the Delaware, limited New Jersey 
to a small area ; similarly, Virginia limited Maryland, and Mary- 
land limited Delaware. Still more striking is the effect of the 
north-south trend of the Champlain-Hudson valley, whereby 
New York gained possession of all the western background of 
the New England states; hence these states are small, and for the 
same reason Vermont was in part colonized from the west. 

It is no accident that three chief ports of our Atlantic coast, 
New York, Philadelphia, and Baltimore, are opposite the nar- 
row, low, interrupted middle part of the older Appalachi- 
ans. It is natural to find that the broader and more mountain- 
ous extremities of the Appalachians are of slow development; 
Maine in the northeast, long ago settled, with an overabundance 
of harbors on its ragged coast, is still a wilderness in its rugged, 
forested interior; and North Carolina in the southwest, settled 
about as early as the other colonies, has since then attracted so 
few newcomers to its highland country that its present popula- 
tion is in an exceptionally high proportion native born of native 
born. 

All the Atlantic slope was covered with forest, rarely inter- 
rupted by treeless spaces, but not infrequently devastated by fires.' 
The early settlers had to clear the land for their farms. The 
hilly uplands of the interior were the " backwoods," and the 
daring spirits who penetrated them were the " backwoodsmen " of 
the eighteenth century, the heroes of many a story of adventure. 
Their successors in the nineteenth century were the ^' frontiers- 
men " on the treeless prairies and the plains, about whom an- 
other crop of stories grew up, but of another kind. The heavy 
labor of clearing the trees from the forested eastern slope finds 
its memorials in our forms of speech to-day. The stump of 



12 THE GREAT LAKES AND THE PRAIRIES 

a tree formed a convenient platform for political orators in rural 
districts ; and now a candidate for an office who makes a series 
of speeches before election day is said to ''stump the state." 
Again, the arduous work of rolling logs demanded the aid of 
neighbors: '' If you'll help me roll my logs to-day, I'll help roll 
yours to-morrow " ; and from this '' log-rolling " has come to be 
the phrase to indicate the exchange of political favors, even in 
prairie states where no actual log-rolling was ever done. 

THE GREAT LAKES AND THE PRAIRIES 

An Ancient Coastal Plain. — With the exception of Lake 
Superior, the Great lakes of the St. Lawrence system — Lakes 
Michigan, Huron, Erie, and Ontario — are systematically re- 
lated to an ancient coastal plain which borders the Lauren tian 
highlands of Canada on the south, in that the basins of these 
five lakes — and of Georgian bay on the east of Lake Huron 
and of Green bay on the west of Lake Michigan — he in lowlands 
on the inside and outside of a fairly well-defined cuesta ; the 
two lowlands and the intermediate cuesta being the necessary 
result of long-continued erosion on the heavy series of strata, 
dipping very gently southward and of varying resistance, of 
which the ancient coastal plain consists. 

The Laurentian highlands seem to have served as the old- 
land and foundation for the coastal plain strata. The high- 
lands consist of very ancient crystalline rocks, enormously 
deformed, which had been reduced to small relief before sub- 
mergence caused a change from the erosion of their ancient land 
surface to the deposition of the overlapping marine strata. Fol- 
lowing the later uplift of the compound mass, the stratified 
formations have, during an undetermined number of cycles of 
erosion, been broadly stripped from their foundation ; finally in 
the cycle of erosion preceding the glacial period, two important 



THE NIAGARA CUESTA AND ADJACENT LOWLANDS 13 



groups of weak strata near the base of the whole series were 
reduced to broad lowlands, while an intermediate formation 
of resistant hmestone — known as the Niagara limestone, be- 
cause it forms the capstone of Niagara falls — survived as a 
broad cuesta of low relief. 

The Niagara Cuesta and the Adjacent Lowlands. — The 
boundaries of the oldland, the inner (northern) lowland, the 
Niagara cuesta, and the 
outer (southern) lowland 
do not through their whole 
length trend directly east 
and west, but — all main- 
taining a rude parallehsm 
— turn well northward in 
the middle of the Great 
lakes region. To the 
west of this turn, the 
Laurentian oldland ex- 
tends southward into the 
highlands of northern 
Wisconsin, separated from 
those of Canada by the 
unsystematic and unexplained basin of Lake Superior. Similarly, 
to the east of the turn, an area of crystalline rocks forms the 
mountainous mass of the Adirondack s in northeastern New 
York, separated from the Canadian highlands by the depres- 
sion along which the St. Lawrence river flows northeastward 
to the Atlantic. 

The cuesta-making Niagara limestone thins and weakens 
westward, and its cuesta effectively disappears in the neighbor- 
hood of the Mississippi river. Likewise, it thins and weakens 
eastward, and its cuesta vanishes in west-central New York. 




Fig. 5. Ancient Coastal Plain of Wisconsij 



14 



THE GREAT LAKES AND THE PRAIRIES 




Thus in the broad lowland of central New York the inner and 
outer lowlands become confluent, but at the same time the strata 
of the Appalachian plateau gain strength and thickness eastward, 

and their dissected margin 
incloses the lowland on 
the south; the plateau 
culminates northeastward 
in the Catskill mountains, 
rimmed on the north by 
the Helderberg escarp- 
ment ; here a branch of 
the Erie-Ontario lowland, 
in the form of the subse- 
quent Mohawk valley, 
passes between the Helder- 
berg escarpment on the 
south and the slope of the 
Adirondacks on the north, as has already been described. 

Relation of the Great Lakes to Glaciation. — It appears prob- 
able that in preglacial time — again with the exception of Lake 
Superior — no lakes existed in this region. If Lake Superior 
occupies a graben, as has been supposed, its date of origin is 
unknown. The basins of the other Great lakes seem to be 
closely associated with glaciation; but the share of crustal 
warping, glacial erosion, and drift obstruction in producing them 
has not been determined. Lake Ontario, Georgian bay, and 
Green bay occupy depressions in the inner lowlands; Lakes 
Erie, Huron, and ^Michigan, depressions in the outer lowland ; 
and the Niagara cuesta, often notched into discontinuous rehef, 
separates the two groups ; its escarpment faces the lakes in the 
inner lowland ; its back slope descends gently beneath the lake- 
in the outer lowland. 



EiG. 6. Ancient Coastal Plain of Ontario 
and New York. 



LOB ATE IVIORAINES AND THE DRIFTLESS AREA 15 

The Prairie Plains. — Repeated invasions of Laurentian ice 
sheets southward across the region of the Great lakes into the 
plains of the upper Mississippi and Ohio drdinage river systems, 
produced extensive sheets of till, often 30, 50, or more feet in 
thickness, by which the small preglacial relief of most of this 
region has been very largely concealed. The surface of the till 
sheets presents the aspect of a plain for scores of miles together, 
and the greater part of our prairie plains are of this origin. 
Sometimes the till surface is gently undulating, forming the 
so-called rolling prairie ; occasionally, it is molded in drumlins, 
as in central New York and in southeastern Wisconsin. 'Ter- 
minal moraines in belts a mile or more in breadth, forming ir- 
regular hills and hollows of low relief, with erratic bowlders and 
lakelets in abundance, mark successive pauses during the final 
glacial retreat, and thus separate the outer till sheets of earHer 
development from the inner and later sheets. The moraines are 
of small rehef, but they are often the only hills that are to be 
seen over long distances on the j)rairic i)]ains. Some of the outer- 
most till sheets are maturely dissected even by small insequent 
streams, as in southern Iowa and northern Missouri. All the 
inner sheets still preserve their initial form, hardly affected by 
normal postglacial erosion, except in the immediate vicinity of 
the larger streams. 

Lobate Moraines and the Driftless Area. — The advancing 
ice sheet found a greater uncvenness of surface in the region of 
the Great lakes than farther south; hence the ice became lobate 
near its margin on the prairies ; it advanced farther along the 
axes of depressions which favored its movement, and suffered 
retardation where uplands or highlands stood in its way. As 
a consequence of this, the terminal moraines are arranged in 
curves convex southward where the ice lobes i)ushed forward; 
they unite in northward-pointing cusps where two ice lobes 



i6 



THE GREAT LAKES AND THE PRAIRIES 



came together, as was first recognized by Chamberlin. Thus 
the Great lakes, occupying the deepest parts of the depressions 
along which the ice lobes advanced, and the moraines which 
looped around the ends of the lobes, have a strikingly sympa- 
thetic arrangement. 

A singular result followed from the retardation of the ice sheet 
on the highlands south of Lake Superior, between the far-ad- 
vancing ice lobes of Lake Michigan on the east and of Lake 




Fig. 7. The Glaciated Area of the Northeastern United States. 

Superior on the west. A roughly triangular space, now shared 
by northwest Wisconsin, northeast Iowa, and southeast Min- 
nesota, remained unglaciated ; it is known as the Driftless area, 
and has been well described by Chamberhn and Sahsbury. 
The ice on the north could not reach it ; the ice on the east and 
west passed by it and closed around it on the south. In an 
excursion from Madison, Wis., we shall enter the eastern part 
of the Driftless area, traversing part of the terminal moraine 
of the Green bay glacial lobe on our way out and back. Within 
the area of this lobe are many drumlins, the axes of which diverge 
to the right and left from the mid line of the lobe, thus indicat- 



SHORE LINES AND OUTLETS OF PROGLACIAL LAKES 17 

ing that the motion of the ice was deflected towards its free 
margin. Another important drumhn area occurs in west- 
central New York, which we shall see on our second day out. 

Shore Lines and Outlets of Proglacial Lakes. — It should be 
remembered that the divide between the St. Lawrence and the 
Mississippi systems is vaguely determined for much of its length 
by the "height of land," a broad swell of the till plains, not far 
south of the Great lakes ; and that from the height of land the 
surface slopes gently northward. During the disappearance 
of the Laurentian ice sheet, temporary proglacial lakes of in- 
creasing size occupied the space between the height of land and 
the retreating ice front. They had south-flowing outlets, most 
of which were tributary to the Mississippi system. 

The proglacial lakes tended to increase in area as the ice 
melted back, but the higher lakes abandoned their southward 
outlets and decreased in size when the retreat of the ice margin 
allowed their waters to drain into or to become confluent with 
their lower neighbors. At the same time a slow rise of the land 
in the northeast — proved by the now inclined position of the 
shore Knes left by the proglacial lakes — caused frequent changes 
in lake outline and discharge. Many subordinate geographical 
features of to-day attest these singular events of the past, and are 
best described in terms of their origin. 

The south-flowing outlets of the longer-lasting lakes eroded 
well-defined channels through the till sheets of the prairie plains, 
across the height of land and beyond, to different members of 
the Mississippi system. The little streams that now enter the 
channels from the prairies on either side are strikingly underfit ; 
not simply because the streams are much narrower than the 
channels, but because the small meanders of the streams cannot 
have produced the much larger, smooth-sided curves of the 
channels. The channels indeed maintain full size above the 



1 8 THE GREAT LAKES AND THE PRAIRIES 

head of the present streams up to the height of land, north of 
which the young or submature shore hnes, formed by the lake 
that fed the large outflowing rivers, may be traced right and 
left with greater or less distinctness. Silt deposited from the 
lake waters sometimes cloaks the underlying till of the submerged 
areas and forms a soil of great fertility. 

The shore lines of the proglacial lakes sometimes took the 
form of offshore sand or gravel reefs (bars), which now appear as 
low ridges, sometimes the form of low shore cliffs ; in drumlin 
districts, there is an alternation of cliffs and reefs. Although, Hke 
the terminal moraines, the shore hnes are features of small 
relief, they are significant in a region where the surface is so 
generally a smooth or gently undulating plain. We shall see 
some of the abandoned shore lines south of Lake Erie on the 
fifth day of our Excursion ; and again in North Dakota on our 
eleventh day. 

In some cases the south-flowing outlet of a proglacial lake 
was abandoned in favor of a lower westw^ard or eastward outlet 
along the ice margin to a neighboring lower lake ; here the 
channel that was eroded on the disclosed land surface between 
the lakes ends in a delta plain that was formed in the lower 
lake basin. Rapids and waterfalls were not infrequently de- 
veloped along the outlet channels, where resistant strata were 
discovered beneath the till. As the further retreat of the ice 
front laid bare lower and lower land between two lakes thus 
related, the first connecting outlet would be abandoned for 
a second one farther north ; and so on, as long as these con- 
ditions were maintained. The level at which the second out- 
let began to flow must have been a little lower than that down 
to which the first outlet had then been eroded ; thus a series 
of lower and lower outlets might be formed across a land surface 
between two lakes. We shall see some channels of this kind 



SHORE LINES AND OUTLETS OF PROGLACIAL LAKES 19 



near Syracuse, N.Y., on our second day. Now the outlet 
channels are all dry, except for the little underfit streams that 
enter from the side and wander on the floor, and except for 
small lakes which occasionally occupy the plunge pools below 
the ancient waterfalls. 

One of the longest-lasting southward outlets flowed from 
a great proglacial lake — known as Lake Agassiz and mono- 
graphed by Upham — 




which occupied the broad 
prairie to-day drained by 
Red river from Minnesota 
and North Dakota across 
Canada to Hudson bay ; 
we shall see its plain and 
its several shore lines on 
the eleventh day of our 
Excursion. The shore 
lines are found at differ- 
ent altitudes and all rise 
gradually to the north ; 
their difference of altitude 
is zero at the outlet, where 
they all become essentially confluent, and increases northward : 
thus proving that the rise of land in the north was in progress 
during late glacial time. There is some reason to think that 
the rise is still continued, as we shall note on our fifth day, when 
we pass certain bays, formed by submergence of valleys near 
the southwest end of Lake Erie. 

The large channel eroded by the outlet, River Warren, of 
Lake Agassiz is now followed by the underfit, aggrading Min- 
nesota river. The upper Mississippi, a larger river than the 
Minnesota, follows a wandering course among drift hills, across 



Fig. S. The Glacial Lake Agassiz. 



20 THE GREAT LAKES AND THE PRAIRIES 

till plains and over hard-rock rapids from its many heads in the 
countless morainic lakes of northern Minnesota through the 
central part of that state, and enters the channel of River Warren 
by a young gorge ; yet the combined volume of the Mississippi 
and the Minnesota rivers of to-day, although navigable up to the 
mouth of the Mississippi gorge, is still underfit in relation to the 
great channel that it follows. The Twin Cities of St. Paul and 
Minneapolis stand in intimate relation to these waterways. 
St. Paul is on the upland north of the channel, just below the 
mouth of the Mississippi gorge, and therefore close to the head 
of navigation ; while MinneapoHs is built around the Falls of 
St. Anthony at the head of the gorge, and uses the water power 
there developed in its flour and lumber mills. 

The southwestward outlet of proglacial Lake Superior, the 
channel of which is now occupied by the St. Croix river, joined 
River Warren not far below the entrance of the Mississippi ; 
in postglacial time, the floor of the main channel has been more 
aggraded than that of the St. Croix channel, so that the latter 
river is now ponded, forming Lake St. Croix, next above its 
junction with the Mississippi. Farther south, a large late- 
glacial river coming from the northeast, the channel of which is 
now followed by the Chippewa, caused an active aggradation 
of the Mississippi channel near the Driftless area, and just above 
the low barrier thus formed the Mississippi broadens so as to 
occupy the whole width of its valley, and is there known as Lake 
Pepin. We shall see several of these subordinate features on our 
eighth day. 

Another important proglacial lake outlet, flowing southwest- 
ward from near the southern end of the basin of Lake Michigan, 
in which the proglacial waters stood at a somewhat higher level 
than do those of to-day, ran across the prairies to the Mississippi ; 
the Illinois river now follows the channel thus excavated. In 



ORIGIN OF NIAGARA FALLS 21 

recent years, an artificial canal has been cut through the head 
of the channel near the present lake ; thus some of the water 
from Lake Michigan is now again tributary to the Mississippi, 
and carries with it the drainage of Chicago, as we shall see on 
our sixth day. 

Origin of Niagara Falls. — One of the most remarkable of 
the proglacial lake outlets ran eastward from the great water 
body known as Lake Warren, which overspread the area of the 
upper Great lakes, and cut its channel along the depression 
between the northward slope of the Appalachian plateau margin 
in central New York and the southward slope of the retreating 
ice sheet. As the river thus guided performed the offices of the 
Niagara and the Mohawk, while the St. Lawrence valley was 
blocked by ice, we may give it the provisional name of the 
Niagarawk, on the understanding that the name is purely collo- 
quial and that it is not to be used after our Excursion is over. 
We shall make a local trip southward from Syracuse on our 
second morning to see some curious gorges cut by the Niagarawk 
in the spurs of the plateau. 

As the ice sheet retreated north of the Niagara cuesta in 
western New York, Lake Warren overspread part of the On- 
tario basin. As the ice retreated from the slope of the Appa- 
lachian plateau in central New York the Niagarawk flowed at 
lower and lower levels, and the level of Lake Warren fell with 
it. Finally the sinking lake was dismembered when the Niagara 
cuesta was laid bare. The small (northeastern) part, called 
Lake Iroquois after it became independent of the large part, 
continued to fall as its outlet, which we may now call the 
Mohawk, took lower and lower courses. The larger (western) 
part of Lake Warren was subdivided into the several upper 
lakes, and of these Lake Erie was sustained by the hard lime- 
stones of the cuesta, from which the outfiowinsf river fell 



22 THE GREAT LAKES AND THE PRAIRIES 

to Lake Iroquois in a great cataract; thus Niagara river and 
falls were born. The still further retreat of the ice opened the 
St. Lawrence valley. Then the ^Mohawk outlet was abandoned, 
and Lake Iroquois became Lake Ontario. We shall review 
many of these points on our second and fourth days. 

The Treeless Prairies. — The smaller eastern extension of 
the prairie plains, as in the northwestern half of Ohio, was 
originally forested ; their greater western extent was originally 
treeless, except in the valleys. To-day these primitive condi- 
tions are in part inverted ; for the forests of the Ohio prairie 
plains are for the most part cleared and replaced by farms ; 
while the \'illages on the treeless prairies always have abundant 
groves of trees ; and near the forested uplands be}-ond the hmit 
of glaciation on the south, a natural encroachment of woodland 
is indicated by comparison of earlier and later surveys. 

The cause of treelessness on the true prairies has been much 
discussed. It has been sought in chmatic conditions, in the 
fineness of the prairie soil, and in prairie fires ; but it is still 
disputed. The prairies are not treeless because of insuflicient 
moisture, for their rainfall of about 40 inches annually, xs^ith 
maximum in the summer, is abundant for tree growth ; it is 
only to the west of the gSih meridian that aridity determines 
the treelessness of the Great plains. Winter cold seems in- 
sufficient to prevent tree growth, for forests cover the Laurentian 
highlands, farther north, where the chmate is more severe. 
Fine soil is believed to retard the spontaneous invasion of trees ; 
and fires are well known to kiU out tree growth, while favoring 
the development of herbaceous vegetation. 

Settlement of the Prairies. — It is noteworthy that some of 
the early settlers of the treeless prairies, coming from a region 
originally forested, mistook treelessness for a sign of infer- 
tility, and selected by preference the forested valley bottoms. 



settle:\iext of the prairies 2^ 

which had to be cleared before they could be farmed; it was 
only by experiment that they discovered the great fertiHty of 
the prairies. Little wonder that, when their fertiHty came to be 
appreciated, they were rapidly invaded by the more enterprising 
members of the agricultural population on the hilly Atlantic 
slope, as well as by throngs of immigrants. 

The possible wealth of the great domain in the Ohio basin was 
long ago recognized and foretold. In his " Analysis of a General 
]\Iap of the Middle British Colonies" Lewis Evans wrote in 1755 : 
"Were there nothing at stake between the crowns of Britain 
and France but the lands on that part of Ohio included in tliis 
map, we may reckon it as great a prize as has ever yet been con- 
tended for between two nations. But if we further observe that 
this is scarce a quarter of the valuable land that is contained in 
one continued extent, and the influence that a state vested with 
all the wealth and power that will naturally arise from the 
culture of so great an extent of good land in a happy climate, 
it will make so great an addition to that nation which wins it. 
where there is no third state to hold the balance of power, that 
the loser must ine\dtably sink under his rival. . . . How different 
this from the conceits of those who would represent some single 
colonies as equal to all England. ... as that they might one day 
be able to dispute dominion with England. . . . Supposing 
the colonies were grown rich and powerful, what inducement have 
they to throw off their independency? National ties of blood 
and friendship ; mutual dependencies for support and assistance 
in their ci\dl and military interests with England ; each colony 
ha\ing a particular form of government of its own and the 
jealousy of cither's ha\'ing superiority over the rest, are unsur- 
mountable obstacles to their ever uniting to the prejudice of 
England upon any ambitious views of their own. But. that 
repeated and continued ill-usage, infringements of their dear- 



24 THE GREAT LAKES AND THE PRAIRIES 

bought privileges, sacrificing them to the ambition and intrigues 
of domestic and foreign enemies, may not provoke them to do 
their utmost for their own preservation, I would not pretend to 
say, weak as they are : but while they are treated as members 
of one body and allowed their natural rights, it will be the height 
of madness for them to propose an independency, were they ever 
so strong. If they had any ambitious views, a strong colony of 
a natural enemy to England on their borders would be the only 
article that would render any attempt of independency truly 
dangerous; and for that reason it becomes those who would 
regard the future interests of Britain and its colonies to suppress 
the growth of the French power and not the English in America." 

The continuity and uniformity of this vast prairie region, 
seldom broken by landmarks, hastened its settlement during 
the first half of the nineteenth century, and favored its subdivi- 
sion by the Land Office of the National Government by a rec- 
tangular and not overaocurate system of meridians and parallels, 
a mile apart, which were marked by posts at their corners and 
halves, for convenience of sale. Each square mile is called a 
section ; and a square of 36 sections forms a township. As 
a result of this method of subdivision, nearly all the common 
roads to-day follow the north-south or east-west section fines ; 
it is chiefly the railways that follow oblique lines. 

The flatness of the till sheets often gave trouble to the early 
farmers by detaining the run-ofi' after spring thaws and heavy 
rains : the faint depressions remained too wet for plowing until 
too late in the season for the growth of a good harvest. This 
difficulty has now been greatly reduced by extensive systems 
of ditches, constructed under the direction of drainage com- 
mj'ssions ; a striking economic response to physiographic en- 
vironment. The universal covering of till made it difficult to 
secure stone for road building, and not only the country roads 



BOUNDARIES OF THE GREAT PLAINS 25 

but the streets in the villages as well were next to impassable 
in wet weather. The introduction of vitrified brick as a pave- 
ment for village streets has worked a marked improvement in 
the last twenty years ; but the country roads, made by " road 
machines " which scrape the soil up from either side and heap it 
in the middle, are often hopelessly bad. But again the flatness 
of the prairies has turned to their advantage in facilitating the 
economical construction of single-track steam railways during 
the second half of the nineteenth century, and in favoring the 
development of electric railways during recent years. 

THE GREAT PLAINS 

Boundaries of the Great Plains. — A broad belt of horizontal 
structure, low rehef, dry climate, and treeless surface extends 
northward from Texas across the United States and far beyond 
in Canada. The belt gained the general name of the Great 
plains from early explorers who crossed it on their way to the 
Far West ; and it has never received any better appellation. 
It is sharply Hmited on the west by the Rocky mountains through 
most of its length, with the supplement of some Basin ranges 
in New Mexico. It is vaguely limited on the east, where a 
gradual transition is made near the 96th or 98th meridian to the 
outrunner of the Laurentian highlands in the glaciated pene- 
plain of northern Minnesota, to the drift-covered prairies of 
Iowa and northern Missouri, and to the homologue of the Appa- 
lachian plateau in the Ozark plateau of southern Missouri. 
More significant than change of surface is the eastward increase 
of rainfall from an annual total of less than 18 or 20 inches, with 
a minimum of less than 12 in the arid southern part of the Great 
plains, to a more abundant precipitation east of the 98th meridian. 

The province of the Great plains is traversed by the shallow 
valleys of many east-flowing rivers. It is interrupted by the 



26 THE GREAT PLAINS 

denuded, domelike uplift of the Black hills in South Dakota, 
and invaded by the subdued Ouachita mountains in Oklahoma. 
It is undercut by the denuded district of central Texas, so that 
here, where it is known as the Llano estacado, its eastern border 
is formed by a descending escarpment, elaborately dissected. 
But through all of its vast extent, the broad expanse of a tree- 
less surface of low relief is the dominating characteristic, well 
warranting the name of the Great plains. 

We traverse this extensive province twice: once across its 
northern part on our way west through North Dakota and Mon- 
tana, and again across its middle on our return east through 
Colorado and Kansas ; we thus gain views of two districts of 
unlike physiographic development. 

The Northern Plains. — The northern parts of the Great 
plains in the United States exhibit all the features of a peneplain, 
more or less perfectly developed in the cycle of its erosion, and 
now slightly dissected by the wide-spaced valleys of its revived 
rivers. It has an elevation of about 5000 feet near the mountains 
and of 2000 feet near the Missouri river at Bismarck. A large 
fraction of this part of the Great plains has been invaded by an ice 
sheet from the northeast, even to the base of the Rocky moun- 
tains in northern Montana ; but the ice seems to have been 
almost inert, as it did no great work either in erosion or deposition 
over most of the area; chiefly to the east of the Missouri river 
in the Dakotas are till sheets and terminal moraines of topo- 
graphic importance. 

Far east of the Rocky mountains, where the strata of the plains 
are weak, the surface passed the stage of peneplanation in the 
former cycle of erosion and was reduced over large areas to 
a geographical plain. The few little residual hills that remain, 
sparsely scattered, only serve to emphasize the rule of plana- 
tion by their exception to it. Nearer the mountains, where some 



THE BADLANDS 



27 



of the strata are more resistant and where volcanic rocks are 
not infrequent, the erosion of the former cycle was less com- 
plete, and residual reliefs, chiefly in the form of scarped mesas, 
ragged cuestas, and dike ridges, interrupt the intervening pene- 
plain. The local relief of some of these residuals near the moun- 
tains measures several thousand feet, and thus attests the enor- 
mous erosion that the region thereabouts suffered during its 
peneplanation. The Crazy mountains, maintained by a network 
of dikes, are the strongest of these residual forms ; they will be 




Diagram of Dike and ]\Iesa on the Great Plains. 



seen north of Livingston, Montana, in the morning of the day 
on which we turn south to enter the Yellowstone national park. 

The rivers of the Great plains have incised mature valleys of 
moderate depth, as if in consequence of regional uplift. The 
valley sides are dissected by numerous insequent ravines, known 
as '' coulees" ; the uneven surface thus produced near each river 
is known as the " breaks " ; but a few miles back, the peneplain 
remains undissected ; hence the district must be on the whole 
regarded as young in the present cycle, though its rivers and 
their valleys are already mature. 

The Badlands. — Where the strata are composed of fine-grained 
sands and clays little indurated, the " breaks " are more ex- 
tensively developed into " badlands " — the " mauvaises terres 
pour traverser " of the early French " voyageurs." The notable 
peculiarity of such districts is the fine texture of their dissection 



28 THE GREAT PLAINS 

by elaborately branching insequent valleys and ravines, so that 
a contour line may have a thousand indentations in a mile. 
The cause of so elaborate a dissection is found in the dryness 
of the cHmate, which makes vegetation scanty, and still more in 
the easy removal of the semi-indurated clays and sands by the 
run-off of the occasional rains, so that active though intermittent 
erosion replaces the slow and steady process of soil-creeping over 
the entire surface, and every httle rill of rain water carves its 
own channel. The enormous extent of the intricately eroded 
surface, in which the horizontal strata of the badlands are thus 
exposed, has contributed effectively to the discovery of the 
vertebrate fossils which abound in certain districts; and these 
fossils, taken with certain details of structure — especially 
gravel-filled channels — suffice to show that the strata of the 
badlands are in large part of fluviatile origin, and not lacustrine, 
as was formerly supposed. 

The Central Plains. — The central part of the Great plains 
which occupies eastern Colorado and western Kansas, some- 
times known as the High plains, has a different aspect from the 
northern part, above described. Like the northern part, the 
central part was enormously denuded in an earlier cycle of 
erosion, and thus reduced to the small rehef of old age, but then 
instead of suffering dissection by revived rivers, it suffered burial 
under the deposits of aggrading rivers. Thus the present sur- 
face is widely covered by heavy fluviatile deposits of gravel, 
sand, and clay, which are coarser and thicker near the mountains, 
but which become finer and thinner eastward ; and the residual 
reliefs of the buried peneplain are completely concealed over great 
distances. But the rivers have now returned to the work of 
erosion, and have incised mature valleys beneath the surface 
which they had previously built up ; wet weather side streams 
have dissected the valley sides; the fluviatile plain remains 



OCCUPATION OF THE PLAINS 29 

uncut only at a distance back from the new valleys. Where 
thus preserved in its original form, it is often extraordinarily 
smooth ; a windmill standing by an isolated ranch is seen in the 
distance on the level but convex plain before the ranch comes 
into sight, thus repeating the experience of first seeing the masts 
and then the hull of a vessel on the level but convex plain of 
the sea. 

Occupation of the Plains. — The dryness of the plains assigns 
them chiefly to pastoral occupations; their population is scanty 
and scattered. Cattle raising is their main industry; but it 
may be remembered that the rich grasses of the prairie states 
support vast numbers of cattle on compact farms of compara- 
tively small area, in contrast to the broad domain of a cattle 
ranch over which the herds must range, if they are to subsist 
on the scanty herbage of the plains. Ranch hfe demands horse- 
manship ; many an eastern boy, whose childhood has been 
passed on foot in a manufacturing village, but who goes west 
in early manhood to seek a living, becomes, after a short " ten- 
derfoot " apprenticeship, as proficient in the arts of tracking and 
lassoing, and as expert and enduring a horseman as a nomad 
of the steppes. To-day small automobiles are commonly used 
to cover the long distances that separate outlying ranches from 
the village of their railroad station. 

The rivers that issue from the Rocky mountains are now 
eagerly used to irrigate the adjoining plains, and many pros- 
perous agricultural colonies have thus been estabHshed not 
far east of the mountain base. Dams and irrigating canals were 
at first the work of individual settlers, later of communities and 
districts ; now the most extensive projects are carried out by 
the Reclamation service of the National Government ; in the last 
ten years, seventy-seven milHon dollars, received from the sale 
of pubHc lands, have thus been expended in the western third of 



30 THE WESTERN UNITED STATES 

the United States, and immense sums of money have already 
been received from the sale of dry or desert lands thus irrigated. 
Between the piedmont belt that is reached by abundant irrigating 
streams and the area of increasing rainfall, several hundred miles 
farther east, the plains are driest and most thinly populated. 
Dry farming, an innovation of recent years, is attempted where 
no irrigation is possible. It has not yet been tried through a long 
enough period to make sure that it is more than a precarious 
occupation, sometimes profitable, occasionally disastrous ; it 
is invited more by the low price of arid lands than by the cer- 
tainty of crops ; it can be best practiced by those who have enough 
hope or capital to survive one or two years of failure in two or 
three of success. 

The railroads that cross the Great plains are deservedly the 
subject of marveling comment. A map shows an amazing 
number of lines, each of which seems to go so far with so little 
local support! But close as the competing lines appear to be 
on a map, they are separated by large distances on the ground ; 
and besides an active local traffic they have an enormous long- 
haul business between the center or east of the country and the 
far western states. 

THE WESTERN UNITED STATES 

The Cordilleran Region. — From the Great plains to the 
Pacific coast, there is a complicated succession of mountains 
and plateaus extending south into Mexico and north into Canada, 
for which the general name, Cordilleras of North America, has 
been proposed. The easternmost member of this great complex 
is the Rocky mountain system, which extends from northern 
New Mexico across the United States and far into Canada, 
and is limited on the east by the Great plains and on the west 
by three other members, the Plateau, the Basin range, and the 



STRUCTURE AND ORIGIN 31 

Lava plateaus provinces. The western members of the Cordil- 
leran complex are the Sierra Nevada of California, the Cascade 
range of Oregon and Washington, and the coast range of Cali- 
fornia, Oregon, and Washington, bordering the Pacific. Through- 
out the central part of this extensive region, even the intermont 
basins and plains have an altitude of from 3000 to 6000 feet; 
the mountain summits frequently exceed 10,000 or 12,000 feet; 
the greatest altitudes are reached by Mt. Whitney (14,898 feet) in 
the southern Sierra Nevada in California and by Mts. Massive 
(14,424 feet) and Elbert (14,421 feet) in the Sawatch range of 
the Rocky mountains in Colorado. The contrast between the 
structural complications of the western United States and the 
structural simplicity of the eastern two thirds of the country 
is strikingly illustrated in a long section, which we shall see in 
the National Museum in Washington. 

THE ROCKY MOUNTAIN SYSTEM 

Area and Subdivisions. — The name. Rocky mountains, is 
advisedly hmited to the ranges which rise near the eastern 
border of the system, including, for example, the Front range 
of Colorado, the Big Horn range in Wyoming, and the Lewis 
and Clark range in Montana. The ranges farther west have no 
collective name subordinate to that of their system as a whole ; 
chief among them are the Wasatch range which borders the basin 
of Great Salt lake on the east, the Uinta range which adjoins 
the Plateau province on the north and is singular in trending 
east-west, and the Bitterroot range which divides Montana and 
Idaho. The variety of form in an extensive mountain system 
defies generalization; hence the following statements must be 
understood as open to many exceptions. 

Structure and Origin. — The ranges of the Rocky mountain 
system consist of an ancient and rather even foundation of 



32 THE ROCKY MOUNTAIN SYSTEM 

deformed crystalline rocks, unconformably covered by a heavy 
series of stratified formations, which vary greatly in composition 
and resistance. The compound mass suffered extensive but 
not extreme deformation and great denudation ; it was then 
again thrown into new disorder by warping and faulting, whereby 
the present system of large reliefs was developed and the present 
cycle of erosion was introduced. The evidence of the first def- 
ormation is manifest enough in the abundant outcrops of dis- 
turbed strata ; the evidence of the second and lesser deforma- 
tion, after the action of great erosion on the previously deformed 
mass, is not so manifest, but is found partly in the occurrence of 
upHfted peneplains, as in Colorado, and partly in the lack of sys- 
tematic relation between rock resistance and mountain altitude, 
as in Montana. The weaker structures are now already worn 
down where they were raised in the secondary uplifts, and thus 
exhibit the reduced altitudes which usually characterize their 
feeble resistance ; the resistant structures are more significant 
of a two-cycle origin of their forms, in occurring at small as well 
as at great altitudes. The crystalline rocks as well as the resistant 
sandstones and limestones, truncated by extensive erosion, sink 
into basins about as often as they rise into mountain crests; 
and for this singular behavior no explanation is so reasonable 
as the one above stated — first noted for this region in 1883 — 
namely, a second deformation following the long-continued 
erosion that was introduced by an earlier deformation. 

Special Features of Certain Ranges. — It is characteristic 
of the Rocky mountain system that the secondary warping and 
faulting was frequently not sympathetic with the more pro- 
nounced deformation of earlier date. The disorder introduced 
by the earlier deformation was seldom, as noted above, extreme ; 
it was commonly of large scale, in the form of broad-arching or 
monoclinal flexing, with more or less faulting or extensive over- 



SPECIAL FEATURES OF CERTAIN RANGES 1,7, 

thrusting; seldom in the form of close folding. A grand de- 
velopment of monoclinal flexing, with some faulting and rare 
folding, characterizes the eastern border of the Front range in 
Colorado ; the delimitation between the plains and the mountains 
was effected by this simple structure, but it is essential to note 
that the difference of level introduced by the great flexure was 
essentially obliterated in the first cycle of erosion, and that the 
present difference of altitude between the plains and the moun- 
tains is largely due to the more rapid erosion of the weaker 
strata of the plains after a second uplift without renewed flexing. 
This will be well seen in our excursion from Denver. Broad arch- 
ing is best exemplified in the Uinta range in northeastern Utah ; 
this is the range which is exceptional in its east-west trend ; it 
is historically interesting as the locality from which Powell, over 
forty years ago, drew his inference as to the antecedent origin 
of Green river which traverses the range from north to south; 
while Emmons, at about the same time, explained the same re- 
lation by superposition near the close of a period of erosion and 
deposition by which the earlier broad arching was separated 
from a later uplift which gave the present altitude to the range. 

The Wasatch range, facing Great Salt lake on the east near 
the city of similar name, is a huge synchne with east-west axis, 
enormously reduced in a first cycle of erosion and now diversified 
by subsequent valleys after its renewed massive upHft. The 
great meridional fault, by which these mountains are truncated 
along their west base, is one of the best examples of a later 
deformation which gave the present altitude of the range, but 
was discordant with the earlier one which produced its synclinal 
structure. We shall have good opportunity of seeing the features 
dependent on these two deformations in local excursions during 
our visit to Salt Lake city. 

Overthrusts of extraordinary extent occur in the northern 



34 



THE ROCKY MOUNTAIN SYSTEM 



part of the system, where — in striking contrast to the simple 
monoclinal flexure of the Front range in Colorado — the heavy 
stratified series of the Lewis and Clark range, which there fronts 
the Great plains, was driven a number of miles eastward over 
much younger strata. The irregular escarpment in which the 
resistant overthrust strata now terminate is believed to be the 
result of revived erosion in the present cycle of mountain de- 
velopment — corresponding to the cycle in which the plains 
were peneplained — following extensive erosion in the previous 
cycle, which was introduced by the great overthrust. 

The Y^ellowstone national park is exceptional in being largely 
built up of heavy lava sheets which constitute the most east- 
ern and elevated part of the great lava-covered area which 
occupies so large a surface in Washington, Oregon, and Idaho ; 
the Absaroka range, next east, is built of massive volcanic 
agglomerates. The latter is abundantly dissected ; the former, 
slightly so; hence the scenery of the park is rather that of a 
plateau than that of a mountain range. 

The scenery of the Rocky mountains is disappointing to 
travelers who expect to find in them a repetition of the Alps. 
In spite of possessing many summits that rise more than 14,000 
feet above sea level, their effective relief is diminished by the 
great altitude of the plains or basins from which they are seen. 
The forms of the ranges within the United States are frequently 
massive ; many summits are dulled or rounded by long-lasting 
erosion ; the climate of the region is too dry to supply extensive 
snow fields or to form large glaciers ; but the observer who looks 
to see what these mountains are, instead of what they are not, 
will find much to hold his attention. 

The Interment Basins. — The Rocky mountain system is 
a true mountain chain, in that it contains many basins encircled 
by ranges. The basins are areas of relative depression produced 



THE INTERMONT BASINS 35 

by down-warping or down-faulting in the later period of def- 
ormation; for even the most resistant rock structures dip into 
them and pass beneath the heavy cover of lacustrine or fluviatile 
deposits with which the basins are aggraded. The inclosing 
ranges are trenched by the deep gorges of outflowing rivers, 
which in many cases have an antecedent habit. In some ex- 
amples, the depth of the trench is not sufficient to allow the 
dissection of the basin deposits ; in other examples the trench 
is deeper than the former surface of the basin deposits, so that 
they are now maturely dissected. The San Luis '' valley " in 
southern Colorado and northern New Mexico, the southern- 
most of all the basins, is drained southward by the Rio Grande 
through a deep gorge in the encircling mountains, and represents 
the first type ; its broad floor is undissected ; much water that 
sinks into the unconsolidated strata of the basin filling is now 
regained by artesian wells. The Green river basin of south- 
western Wyoming and northeastern Utah represents the second 
type ; the plain surface of its former fiUing is now thoroughly 
dissected by the branches of Green river, which escapes by a deep 
canyon through the Uinta mountains on the south ; this canyon 
was the first one which Powell and his party descended in boats 
on his memorable exploration of the " Colorado river of the 
West." 

The lofty intermont basins in Colorado are known as '' parks." 
In the afternoon of the day on which we reach Denver, we shall 
cross South park, rimmed on the west by the Mosquito range 
and on the east and north by the highlands of the Front range ; 
its level floor lies at an altitude of nearly 10,000 feet, as yet 
undissected by its river, the South Platte, which flows north- 
eastward through a rapidly descending gorge. Directly west 
of South park lies the deeper and narrower basin of the upper 
Arkansas, between the Sawatch range on the west and the 



36 THE ROCKY MOUNTAIN SYSTEM 

Mosquito range on the east. We shall have a fine view of this 
aggraded basin on the day of our approach to Denver ; the day 
after leaving Denver, we shall see the Royal gorge by which the 
Arkansas passes through the Front range from the southern 
end of the basin. 

Drainage of the Rocky Mountain System. — The irregular 
grouping of mountain ranges and depressed basins results in 
producing a complicated interlocking between the headwaters 
of the several river systems by which the region is drained. 
The long Missouri-Mississippi system and its. branches, the 
Platte and Arkansas, receive the outflow of many basins that 
discharge eastward to the plains ; the Rio Grande carries south- 
ward the w^aters of the San Luis '' valley " ; the Colorado 
receives from its chief branches, the Green and the Grand, which 
rise in the southwestern ranges and basins, the large volume that 
enables it to traverse the deserts of the far Southwest ; several 
small rivers flow westward into the basin of Great Salt lake; 
and the tributaries of the Columbia carry off the drainage of the 
northwestern part of the system in Montana and Idaho. We 
shall see something of all these rivers in one part or another of 
our journey. We shall first cross the continental divide on our 
way westward between the Missouri and Columbia systems, 
after leaving the Yellowstone national park; we shall cross it 
again on our way eastward between the headwaters of the Grand- 
Colorado and the Arkansas-Mississippi; we shall ascend to the 
divide in a local excursion from Denver; and we shall cross it, 
going and returning, in the Plateau province. 

Two features of interest regarding the divide between the 
Columbia and Missouri-Mississippi systems deserve special 
mention. A branch of the former in northern Montana has its 
head at the eastern base of the mountains, and passes through 
their whole breadth on its way to the Pacific ; it receives indeed 



DRAINAGE OF THE ROCKY MOUNTAIN SYSTEM 



37 



the drainage of a small area of the plains, and is destined to 
receive more, for its westward descent is much more rapid than 
the eastward descent of its Missouri-Mississippi competitor. 
It is noteworthy that this exceptional case lies in the region of 
the great overthrust, and it may be in consequence of it. The 
Great Northern railway utilizes the deep-cut pass thus made; 
it ascends the long slope of gently inclined plains, and begins 
its westward descent at the eastern base of the mountains. 




Fig. io. Falls of the Yellowstone River. 

The sources of the Snake river, the largest tributary of the 
Columbia, rise in the lava plateaus of the Yellowstone national 
park. They formerly received the outflow of Yellowstone lake ; 
but, as first announced by Goode, the Y^ellowstone river gnawed 
by retrogressive headwater erosion through the rim of the lake 
basin on the northeast and thus captured the lake waters, which 
thereupon abandoned their former westward outflow and rapidly 
intrenched their new course, which we shall see in the Yellow- 
stone canyon on the last days of our visit to the park. This 



38 THE ROCKY MOUNTAIN SYSTEM 

is an excellent example of a recent capture, for the diverted lake 
outlet has not yet had time to grade its new course; the lofty 
falls of the Y'ellowstone plunge into the head of their narrow 
canyon. A little west of the lake, a lateral stream has built 
an alluvial fan across the narrow valley floor of the former lake 
outlet ; the fan now forms a part of the continental divide, and 
its stream, sometimes following a radius which leads it to Atlantic 
drainage, sometimes to Pacific drainage, is therefore known as 
" Two-ocean creek." 

Features due to Glaciation. — Existing glaciers in the Rocky 
mountain system within the United States are of small dimen- 
sions. The largest are in the Lewis and Clark range of northern 
Montana ; here a district has recently been set apart as Glacier 
national park ; it unfortunately lies outside of our route. 

The large and abundant glaciers of the Glacial period have left 
manifest traces of their work in valley-head cirques and sharp- 
ened peaks, in overdeepened troughs and hanging lateral valleys, 
and in terminal moraines, as well as in cirque-basin and trough- 
bottom lakes. In the ranges of Colorado, the enlargement of 
valley-head cirques sometimes succeeded, but frequently failed, 
in sharpening the summits that had been given rounded forms 
by normal preglacial erosion ; the glaciers there wTre long enough 
to descend into the intermont basins, as in the upper valley 
of the Arkansas, where we shall see their terminal moraines; 
but they were not long enough to descend to the plains at the 
eastern mountain base. In northern Montana, the valley-head 
cirques are much larger ; their enlargement has frequently ob- 
literated all traces of preglacial summit form ; their troughs 
reach to the eastern mountain base and their terminal moraines 
advance on the plains, where, singularly enough, these piedmont 
glaciers encountered the margin of the vast Laurentian ice sheet 
which overran the plains from far northeast. 



SETTLEMENT 39 

An interesting question of terminology is associated with the 
normal and glacial mountain forms of this region. Many of 
the Rocky mountains have been so well subdued that their 
domelike summits and rounded spurs might be given the name 
of '' Mittelgebirgsformen/' even though they reach altitudes 
of 11,000 or 12,000 feet, which would place them among " Hoch- 
gebirge." It is only to summits of somewhat greater altitude, 
which like their fellows were very generally subdued and rounded 
in preglacial time, but which now in consequence of glacial 
sapping and sharpening have gained Alpine boldness, that the 
name, " Hochgebirgsformen," may be apphed. It should 
be remembered that excellent " Hochgebirgsformen "are found 
in the mountains of Spitzbergen at the moderate altitudes of 
" Mittelgebirge," because of the intense glaciation that has there 
taken place, and we here see that many summits in the Rocky 
mountains have '' Mittelgebirgsformen," although their height 
would warrant their being classed with '/ Hochgebirgen " ; hence 
it would seem to be advisable to give up these empirical terms, 
which find inductive justification only within the small area of 
central Europe, and to introduce either empirical terms that 
better represent the facts of broader observation, or explanatory 
terms that adequately represent the development of mountain 
forms. 

Settlement. — The mountain ranges of the Rocky mountain 
region have been more thoroughly explored by the prospector 
with his pick than by the geologist with his hammer. Ore de- 
posits are abundant. Numerous mining camps have sprung up ; 
many of them have been short-Hved and are now in ruins ; 
others of greater endurance have rich gold or silver ores, as 
at Leadville and Cripple Creek in Colorado, or copper ores, 
as in the subdued ranges near Butte in Montana. Agricultural 
settlements in the intermont basins promise to be more per- 



40 THE ROCKY MOUNTAIN SYSTEM 

manent ; they are frequently well supplied with streams, which 
furnish electric power during their descent in the mountain 
flanks, and feed irrigation canals on the basin floor. The forests of 
the mountain sides are of increasing value, and are now largely 
under inspection of our Forest service ; but they have been 
fearfully devastated by fires, many of which have been due to 
rank carelessness. Overlarge flocks of sheep have yielded great 
profit to their owners, but they have often caused devastation 
by uprooting the scanty herbage on mountain slopes. 

The habit of using meridians and parallels, for the early 
definition of boundaries in unsurveyed regions finds abundant 
application in the western United States. On the prairies and 
the plains, such boundaries are not inconvenient ; and in so 
far as they were used to define territorial Hmits in advance of 
explorations and surveys, they served an excellent purpose even 
in the mountains. But with the increase of population bound- 
aries of this kind introduce many practical difficulties. The 
division of the public lands in the mountain region into square- 
mile sections has repeatedly resulted in awkward property fines ; 
as when a valley head is included in a section of which the greater 
area lies on the other side of the dividing ridges ; and cases are 
known in which state or international boundaries cut off a high- 
walled cirque from the trough into which it opens, and associate 
it with other troughs from which it is separated by almost 
unscalable cliffs. 

There are now six railroad lines which cross the Rocky moun- 
tains, and other lines are in the building or prospect. Their 
construction has involved serious engineering problems, but 
nothing so difficult or so expensive as the great tunnels through 
the Alps. The first line, the Union Pacific railway, finished 
nearly half a century ago, traversed the Front range in southern 
Wyoming, where the local relief of the arched peneplain in the 



LOCATION AND STRUCTURE 41 

mountain crest is so small that many a traveler crosses it 
without knowing that he is in the Rocky mountains. On other 
lines, it has been a not uncommon practice to cross a pass by a 
temporary Kne, which is afterwards abandoned for a tunnel 
at a lower level. 

THE PLATEAU PROVINCE 

Location and Structure. — Southwest of the Rocky moun- 
tain system and east of the Basin range province, there is an 
elevated region occupied by a heavy series of horizontal strata, 
in which the leading features are extensive plateaus of moderate 
local relief, standing at different altitudes and separated by long 
escarpments; this is the Plateau province. Its altitude varies 
between 5000 or 6000 and 11,000 or 12,000 feet; it is here and 
there bedecked by volcanoes and lava flows in various stages of 
dissection, and it is occasionally trenched by profound canyons. 
Its climate is dry and its surface is for the most part treeless; 
forests occur only at altitudes above 7000 or 8000 feet. Its 
population is scanty and scattered. 

The Plateau province is structurally subdivided by faults 
and monoclinal flexures, generally trending about north-south, 
by which adjacent masses or ' blocks " have been raised to 
different altitudes. The region is no longer in its first cycle of ero- 
sion, but in the early stages of a second cycle that was introduced, 
after the attainment of an advanced stage of erosion in the first 
cycle, by strong regional uplift — probably about synchronous 
with the later deformation of the Rocky mountain system — 
with moderate or negligible movement on the earlier lines of 
displacement. Hence the present plateaus frequently exhibit 
broadly stripped surfaces of erosion, which coincide rather 
closely with a resistant formation. We shall see a fine example 
of a stripped highland surface in the Kaibab plateau and its 



42 THE PLATEAU PROVINCE 

southern extension, the Coconino, during our stop at the Grand 
canyon of the Colorado, which cuts off the lower and smaller 
part of this single structural element from the higher northern 
part. The Kaibab block is structurally separated by an east- 
dipping flexure from a lower stripped plateau, the " Marble 
platform," on the east, and by a strong fault from another 
stripped plateau, the Kanab plateau, on the west ; but it must 
be remembered, as will be further explained below, that since 
these dislocations were produced, great denudation has taken 
place, followed by renewed uplift ; it was the latter uplift which 
introduced the present cycle of erosion, a cycle that is so little 
advanced that nearly all of its valleys are young or submature 
canyons. 

Escarpments. — The escarpments of the Plateau province 
are of two classes. Those of the first class are the result of ad- 
vanced normal erosion, chiefly in the first cycle, on horizontal 
or gently inclined strata of varying resistance, with refreshment 
by renewal of erosion after the later uplift. As the plateau- 
making strata, although of great thickness, have but five or six 
important alternations between strong capping formations and 
weak sapping formations, the erosional escarpments within the 
hmits of each plateau block are few in number and of strong 
relief ; they are usually irregular, sometimes ragged in outline. 
Where the forms of the first cycle are still preserved, as occasion- 
ally happens far from the present canyons, the escarpments have 
the dulled form of late maturity; but where renewed erosion 
has caused active sapping, the escarpments are steep and bold ; 
extensive landslides occasionally accompany the refreshment of 
form thus introduced. 

In the mature erosion of a typical plateau of essentially hori- 
zontal structure, a platform gently ascends from the top of one 
escarpment to the base of the next higher one. This is the case 



ESCARPMENTS 



43 



to the north of the three stripped plateaus above mentioned, 
where a series of south-facing escarpments of strong rehef rises 
Hke a flight of gigantic steps to the highest plateaus of the prov- 
ince in southern Utah ; the escarpments are for the most part 
steepened by the revived erosion of the present cycle, but by far 
the greater part of the erosion by which their strata were stripped 
from the lower plateaus on the south was accomplished during 
the earlier cycle, when the whole region stood lower than now. 

In other parts of the province where the structure is gently 
inclined, the platform which crowns an escarpment descends 
through a long back slope ; and the steep face and the long back 
slope taken together give the relief of a typical cuesta. The 
finest examples of this kind occur in a northeastern subdivision 
of the province, which we shall cross on the way from Utah to 
Colorado, a subdivision which was called by Button the San 
Rafael swell, because of its gently domed structure. It has been 
enormously denuded, and its harder members now form ragged 
cuestas disposed in irregularly concentric ovals. In this district 
occur the laccoliths of the Henry mountains, made famous by 
Gilbert's early studies. Our route here lies north of the center 
of uplift and follows — mostly at night — a broad subsequent 
depression between the back slope of one cuesta on the south 
and the lofty and elaborately dissected scarp of another on the 
north ; the latter is known as the Book cliffs and is one of the 
strongest features of its kind in the whole province. The eastern 
part of the swell is traversed by the Green river, which, after 
joining with the Grand, forms the Colorado ; all these rivers 
follow inconsequent courses, which led Powell to regard them 
as antecedent ; some other explanation may perhaps be found 
in connection with the long period of erosion which followed 
the doming of the structure, and with the broad uphft which 
introduced the present cycle. 



44 THE PLATEAU PROVINCE 

The escarpments of the second class are associated with faults, 
and like the escarpments of the first class are subdivisible into 
two kinds. The simpler kind includes escarpments which have 
been produced directly by faulting, although the fault face may 
now be more or less maturely dissected. These may be called 
fault scarps ; their height during the earlier stages of their cycle 
is a good measure of the faulting. Scarps of this kind must have 
been common in the early stages of the first cycle through which 
the Plateau province has passed; but they are relatively rare 
to-day, being now limited to localities where new or renewed 
faulting was associated with the introduction of the second cycle. 
Chief among the latter is the maturely dissected fault scarp 
by which the Plateau province is separated from the less elevated 
Basin range province on the southwest; we pass this great 
escarpment twice, on our way from the Colorado canyon to 
Phoenix in southern Arizona, and on the return ; but at night 
on both trips; we shall see it from the Roosevelt dam. 

The second kind of escarpments associated with faults is 
more abundant to-day; it includes those examples which are 
developed by the erosion of a second cycle acting unequally on 
different parts of a broadly upHf ted peneplain — or subdued 
surface of late maturity — that had been worn down on a faulted 
structure in a preceding cycle. Wherever weak strata stand 
next to resistant strata along a fault line in such a worn-down 
surface, the more rapid removal of the weaker strata necessarily 
results in the development of a scarp, which must be maintained 
for a time close to the fault fine by the resistant strata; 
hence the scarps of the second kind may be called fault-line 
scarps, in distinction to the fault scarps of the first kind. The 
altitude of fault-hne scarps is not a measure of the faulting, as it is 
in fault scarps, but of the thickness of the weak strata removed 
by renewed erosion. The slope of a fault-fine scarp is not 



MONOCLINAL FLEXURES 



45 



necessarily directed toward the down-thrown block, but towards 
the weaker strata, which may occupy either the uphfted or the 
down-thrown block. If the weak strata are in the down-thrown 
block, the renewed fault-hne scarp may be called resequent; 
if on the opposite side, obsequent. Resequent fault-Hne scarps 
are abundant in the Plateau province ; obsequent examples 
are of rarer occurrence. The abrupt descent of the Kaibab 
plateau to the lower Kanab plateau on the west is a dissected 




Fig. II. Hurricane Ledge, a dissected Fault-line Scarp. 



resequent fault-Hne scarp ; the western border of the Uinkaret 
plateau, west of the Kanab, is another fault-Hne scarp, known as 
Hurricane ledge. 

Monoclinal Flexures. — Peculiar features occur where the 
plateau blocks are separated by monoclinal flexures instead of 
by faults. If the erosion of the two cycles is such that the land 
surface of to-day is determined by a single resistant formation, 
stripped of the originally overlying weak strata on both sides 
of a flexure, the flexure will be revealed in the existing form, 
more or less ripped by consequent ravines and gorges; the eastern 
border of the Kaibab plateau, where its heavy limestones descend 



46 THE PLATEAU PROVINCE 

to the Marble platform on the east, is of this kind. But if the 
flexed structures were worn down to low rehef in the first cycle 
of erosion, in such a manner that a resistant stratum plunges 
down at the flexure, separating weaker strata on either side, 
then when uplift and renewed erosion are introduced, the 
plunging monoclinal formation may assume a greater or less 
relief in a rectihnear ridge between two lowland belts. An 
extraordinarily fine example of this kind is found near the 
Arizona-New Mexico fine on the Nutria monoclinal flexure, 
admirably described by Button ; we shall probably make a brief 
stop on it. 

Volcanic Features. — The volcanic features of the Plateau 
province are abundant and varied. Young cinder cones and lava 




Fig. 12. Lava Flows on the Plateaus of Arizona. 

flows occur on the plateaus north and south of the Colorado 
canyon ; some of the flows are so recent that they cascaded into 
the canyon after it had been eroded to about its present depth 
at a point fifty miles or more west of the place where we visit 
it, and obstructed the river for a time. They have now been 
cut through, but their remnants are still clearly seen clinging 
to the canyon wall. Great volcanoes, now elaborately dissected 



VOLCANIC FEATURES 47 

or reduced to unevenly subdued forms, are scattered over the 
stripped plateaus. Mt. Taylor is one of these ; it surmounts 
a lava-covered plateau in northwestern New Mexico, north of 
our route ; the surrounding surface, free from protective lava, 
is worn down to a lower level. Many volcanic necks occur in 
this worn-down district, as if the present surface were below the 
surface at the time of volcanic action. Mt. San Francisco in 
north-central Arizona forms a noble landmark over the arid 
plateau to the north of our route on the morning of our approach 




Fig. 13. Volcanic Buttes near Mt. Taylor. 

to the Colorado canyon ; its Alpine flora includes several species 
of plants identical with those found in northern Greenland. 
Some of the most lofty members of the Plateau province, for 
example, the Awapa plateau in southern Utah, in which the 
highest members of the great sedimentary series of the Plateau 
province are found, appears to have been preserved from the 
widespread erosion which removed the rest by a heavy capping 
of lava. This plateau stands at an altitude of nearly 12,000 feet ; 
it is covered by a fine coniferous forest ; from its southern cliffs 
one may descend across successive normal retreating escarpments 
to the broadly stripped plateau of northern Arizona — unfortu- 



48 THE PLATEAU PROVINCE 

nately named the '' Colorado plateau " — in which the Colorado 
canyon is intrenched. 

Canyons. — The canyons for which the Plateau province is 
justly famous are the work of revived rivers in the present cycle 
of erosion. They seldom follow fault lines; the Grand canyon 
of the Colorado traverses northwestern Arizona in an irregular 
southwestward course, with little regard for several strong 
flexures and faults of meridional trend. The work of the present 
cycle is so httle advanced that many tributary streams have 
not yet cut down their upper courses significantly below the 
surface of the uplifted plateaus, and vast areas — lowlands of 
the former cycle, plateaus of the current cycle — are therefore 
still undissected with respect to present baselevel. This we 
shall see as we follow the Little Colorado river soon after enter- 
ing Arizona. Yet even the smaller tributaries of the large, deeply 
intrenched rivers have cut down side canyons so effectively 
toward their mouth that they have already established accordant 
junctions with the master river ; none but the smallest tribu- 
taries fall from normally hanging side valleys, in which an ac- 
cordant junction with the main canyon bottom is not yet 
estabhshed. 

Only in exceptional cases are the canyons of the present cycle 
narrow slits with vertical walls ; the best example of this kind 
is the canyon of Virgin river, a branch of the Colorado in south- 
western Utah, where the entire depth of the canyon is cut in 
massive and resistant sandstones. Most of the canyons are 
submaturely opened, because the intrenchment of their rivers 
has disclosed an alternation of resistant and weak formations ; 
the latter have worn back into slopes, and force the cliffs of the 
former to retreat. It is particularly in the magnificent disclosure 
of crustal structure afforded in escarpments and canyon walls 
that the immediate relation of structure and form is here made 



SETTLEMENT 49 

apparent, even to the geologically uninitiated observer ; so 
that the whole population of this region is predisposed towards 
an understanding of the leading principles of earth sculpture, 
and the geologists who first explored it involuntarily became 
physical geographers. 

Yet even in the widest canyon, the contrast between the work 
of excavation now accomplished and the widespread denuda- 
tion which remains to be accomphshed in the removal of the 
bordering plateaus enforces the youthfulness of the present 
cycle upon the observer's attention. If one hesitates to believe 
that so vast a task as the removal of broad plateaus can ever 
be accomphshed, the recognition of the origin of the broad 
plateau surface, itself the product of an essentially completed 
cycle of erosion before the excavation of the canyon was begun, 
is an excellent antidote to such skepticism. And for those who 
look deeper, there are buried plains of erosion, long preserved 
and now revealed as geographical fossils in the bottom of the 
Grand canyon, which are silent but eloquent witnesses to the 
verity of completed cycles of erosion in the earth's history. 

Settlement. — The Plateau province seems destined to remain 
a thinly inhabited region, in which the annual visitors to its 
scenic wonders almost outnumber its fixed population. As 
the home of ancient cliff dwellers and as the site of many pueblos 
on the natural strongholds of mesas, it possesses a great ar- 
cheological and ethnological interest ; as a region of dry cHmate, 
it attracts and cures many consumptives, known as '' lungers " 
in local slang. Its fuller occupation demands irrigation, and irri- 
gation is difficult or impossible in a plateau country, where most 
of the few rivers flow in deeply intrenched canyons. The new- 
comer repeatedly says : '' If water could only be led over this 
dry country! " — before he is reconciled to take things as they 
are and make the best of them. Rivers, which so generally 



50 THE BASIN RANGE PROVINCE 

prepare pathways for travel and traffic, here form inverted 
barriers; the Grand canyon of the Colorado has been well 
characterized as '' a mountain range of nothing, upside down." 
It cuts off the northern part of Arizona disadvantageously 
from the rest. 

THE BASIN RANGE PROVINCE 

Boundaries of the Province. — Systematically considered, 
this province is an arid region of disordered structure, with 
abundant volcanic rocks in the northern and western parts. 
According to Gilbert, it was reduced to subdued or low rehef 
in the cycle of erosion introduced by the deformation of its 
structure, then broken into great blocks, commonly measuring 
from lo to 30 miles east and west, and from 50 to 100 miles 
north and south, and diversely displaced and tilted; the up- 
lifted blocks now being so elaborately dissected that they show 
few traces of their upHfted form, and the depressed blocks being 
buried out of sight by the waste from the uplifted blocks. 

The northern part of the province is abruptly limited on the 
west by the dissected fault scarp of the Sierra Nevada ; on the 
cast by the dissected fault scarp of the Wasatch range — the 
westernmost member of the Rocky mountain system in this 
latitude — and of the Plateau province next south ; on the north 
there seems to be a gradual transition to the little disturbed 
ava plateaus of Idaho and Oregon ; to the south, the province 
widens, passing around the end of the Sierra Nevada to the Pacific 
coast, and around the Plateau province and the southern end 
of the Rocky mountains to the Great plains in central New Mexico, 
and then slowly narrowing again and reaching far across the in- 
ternational boundary into the Republic of Mexico. In the 
north, some of the faulted and tilted blocks are little dissected, 
as if that region had been lately invaded by block-making def- 



FAULT-BLOCK MOUNTAINS 



51 



ormation ; to the south, in Arizona, some of the ranges are so 
greatly worn down that their residual cores are bordered with 
smooth rock floors, thinly veneered with alluvium. 

The most striking topographic feature of this great province 
is the isolation of its separate ranges. Many of them have a 
marked individuahty, standing well apart from their fellows, 
the intermont spaces being occupied by the broad alluvial floors 
of the aggraded depressions. In this respect the Basin range 
province is in strong contrast to the Rocky mountain system, 
in which the basins with their aggraded floors are isolated from 
one another by the continuous complex of mountain ranges. 

Fault-block Mountains. — The detailed features of a tilted 
fault-block mountain range in the young or submature stage 




14. Diagram of a dissected Block Mountain and a Waste-filled Trough. 



of its new cycle are: i. the want of connection between the 
general trend of the range and the strike of its rock structure ; 
2. the gradual fall of the back slope, in which the prefaulting 
surface, now more or less dissected, descends from the crest of 
the tilted block to an irregular base, where it disappears under 
the alluvium, so that the hardest rocks may occur at any altitude ; 



52 THE BASIN RANGE PROVINCE 

3. the truncation of all structures along the simple but not 
necessarily rectilinear base of the fault face, remnants of which 
are still to be seen, little changed, in the triangular facets of spur 
ends between narrow ravine mouths; while the upper part of 
the fault face is destroyed by the widening of the ravines, and the 
crest is pushed back and notched by the recession of the ravine 
heads ; 4. the outspreading bowlder-strewn fans of waste that 
are built far forw^ard from each ravine mouth into the broad inter- 
mont depressions ; while one is ascending the long, gentle slope 
of such a fan, his eye comes to misjudge its inclination, taking 
it for more nearly level than it really is ; and if an irrigating 
ditch is then met, the water in it seems to be running up hill ; 
5. the frequent indication of renewed faulting that is found in 
rectilinear scarps traversing the gravel fans near and parallel 
to the mountain base. 

In the later stages of its cycle of erosion, a fault-block moun- 
tain must lose many of these features ; the mountain base must 
retreat from the fault hne, the ravines must widen, the spur ends 
must lose their triangular facets and become rounded ; the back 
slope must lose all traces of the pre- faulting form, and the stronger 
structures must be left in rehef as subsequent valleys are ex- 
cavated along the weaker structures ; but still the resistant struc- 
tures that remain in strongest relief in the range crest may 
descend slowly to the base of the back slope, where they dis- 
appear under alluvium. In a far-advanced stage of the cycle, the 
residual hills of a fault-block range would terminate vaguely in 
sprawling spurs, having no necessary relation to the initial relief 
or to the fault Hne. As already intimated, there is some reason 
for thinking that the Basin range province includes examples 
of fault blocks in all stages of erosion. 

Climate of the Basin Range Province. — The aridity of this 
region deserves further emphasis. The mountains sometimes 



CLIMATE OF THE BASIN RANGE PROVINCE 53 

support tree growth, but the intervening plains have only a 
desert vegetation, in which sagebrush and many kinds of cactus 
abound. There is but one large river, the Colorado, which 
flows from its sources in the Rocky mountains across the prov- 
ince to its mouth at the present head of the Gulf of Cali- 
fornia ; the " present head " being here specified, because the 
former head of the gulf, cut off by the delta of the Colorado, is 
now evaporated to a dry and flat basin floor, sKghtly below sea 
level ; formerly a desert, but destined to reclamation by irri- 
gation. All the other streams of the region disappear within it ; 
hence it contains many basins of interior drainage, and from 
this feature as well as its numerous mountains, its name is de- 
rived. 

The altitude of the intermont alluvial plains in the northern 
part of the province, which we cross between San Francisco and 
Salt Lake city, varies from 4000 to 5000 feet ; and from this 
district there is a general loss of height south and southwestward. 
It is therefore not by reason of inclosure by mountain barriers 
but because of insufficient rainfall that all the drainage of the 
Basin range province does not join the Colorado river and reach 
the sea. Most of the streams wither away on the gravelly slopes 
of the intermont depressions soon after leaving the ravines and 
valleys in the discontinuous ranges ; these Httle streams often 
show a diurnal fluctuation, shrinking into their ravines during 
the noon hours of unclouded sunshine and active evaporation, 
and advancing beyond the mountain base only during the cooler 
hours of the nights ; occasionally a small trunk stream is formed 
along the axis of a depression, dwindling as it flows, and at last 
vanishing, even on a forward slope, in the hot and dry summer 
weather; or flowing farther after rains in the winter or spring 
and then ending in a shallow water sheet on a smooth clay floor, 
or playa. 



54 



THE BASIN RANGE PROVINCE 



Shore Lines of Extinct Lakes. — The well-preserved shore lines 
of recently extinct lakes — named Lakes Bonneville and La- 
bontan, after early explorers of the region — are features of 
detail in the northeast and northwest part of the Basin range 
province, made well known through the monographs of Gilbert 
and Russell. The lakes were of extremely irregular outHne, 




Fig. 15. Lakes Lahontan and Bonneville. 



as they rose upon the discontinuous mountain ranges ; Bonne- 
ville measured about 300 miles north-south, and Labontan over 
200. The shore-line features include cliffs, beaches, beach ridges, 
V-bars, and deltas ; these features now stand at various altitudes 
up to nearly 900 feet above the basin floors, thus indicating great 
fluctuations of lake level. The highest beaches of Bonneville 
mark the level of an outlet to the north, by which its waters 
temporarily overflowed to the Snake-Columbia system. We 
shall see many of these curious features as we cross Nevada and 
while we are at Salt Lake. 



POPULATION 55 

Population. — The population of this province is concen- 
trated about mines in the ranges and upon irrigated farms of 
restricted area on the intermont plains. Great spaces are un- 
inhabited and must remain so. There is no water to irrigate 
them. The mining towns wax rapidly during a period of in- 
creasing production, and then wane as the yield of the mines 
falls offo Virginia city in western Nevada is now a waning 
town of this kind, but, in 1880, it had a population of about 
11,000; $350,000,000 worth of gold and silver has been taken 
from its mines on the famous Comstock lode. Goldlield, in 
one of the north-central ranges, is of more modern date, still 
growing. Rich copper mines are worked in the mountains of 
southern Arizona. 

The irrigated districts, commonly known as " settlements," 
but fully deserving to be called " oases," are more steadily 
prosperous ; Salt Lake city, Ogden, and Provo, all of which are 
on our route, are the best examples. Many of the smaller 
settlements have reached the limit of agricultural population ; 
others, in which large reclamation works have been lately 
established, have a promising future, as we shall see at Phoenix, 
Arizona. 

The daring enterprise of American railroad construction 
is nowhere better illustrated than in the Basin range province. 
It was surprising enough on the Great plains ; it is amazing on 
the intermont deserts, where the lines traverse seemingly end- 
less vacancy in order to connect distant centers of population. 
The line which we take from San Francisco to Salt Lake city, 
originally known as Central Pacific railroad, but now operated 
by the Southern Pacific company, was a bold project when it 
was constructed forty-five years ago ; this line, with the Union 
Pacific line from Omaha to Salt Lake, made the first " Pacific 
railroad," and awakened a world-wide attention. Now six other 



56 THE LAVA PLATEAUS 

main lines cross the Cordilleran region, and the construction 
of the last one, which closely parallels the first through the deserts 
of the Basin range province, was unnoticed except by those 
immediately interested in it. 

THE LAVA PLATEAUS 

General Features. — North of the Basin range province, 
between the Rocky mountain system on the east and the Cascade 
range on the west, lies a region about as large as France, covered 
with lava. A vast period of time must have elapsed during the 
accumulation of the heavy series of lava flows, for the deep 
canyon of Snake river between Idaho and Oregon discloses the 
petrified remains of forests which grew at many successive hori- 
zons in soils formed on the lava and ash beds. The inequalities 
of the preexistent surface are sometimes revealed in the same 
canyon, where the river has cut through the lavas to their uneven 
foundation, and there the canyon narrows. The border of some 
of the younger flows in the eastern part of the region contours 
around advancing mountain spurs and forms embayments in 
valleys ; and isolated mountains occasionally rise above the 
lava surface. But although certain parts of the lava plains have 
a recent appearance, other parts must be of relatively ancient 
origin ; for some districts have been dislocated by strong mono- 
clinal flexures and faults.. Some of the lava masses that are 
thus displaced form young block mountains, as in southern 
Oregon, a district made classic by Russell's vivid descriptions ; 
the mountain blocks are little dissected, and the depressions 
between them contain numerous lakes ; the Klamath lakes, 
which we shall pass the day before reaching San Francisco, 
belong here. Other displacements are, however, much older, 
for the reHef that they initiated has been almost destroyed by 
normal erosion, as we shall see at Coulee city, the day before 



THE CASCADE RANGE 57 

reaching Seattle. Part of the lava-covered region has been 
broadly upHfted and elaborately dissected, as in the so-called 
Blue mountains of southeastern Washington and northeastern 
Oregon. Moreover, other lava fields, which may be regarded as 
extensions of those in this province, have been uplifted in the 
Rocky mountains, where they form the highlands of the Yellow- 
stone national park ; and a western portion of the lava fields 
has been upHfted in the Cascade range, where there has been 
abundant dissection after upHft. 

The Lava plateaus are drained by the Columbia, which enters 
from the ranges of Canada on the northeast, and by its chief 
tributary, the Snake, which comes from the Rocky mountains 
on the east. Both rivers have strongly intrenched courses ; part 
of the canyon of the Snake, with benched walls of lava flows 
and ash beds, is only less remarkable than that of the Colorado. 

During the glacial period, the great bend of the Columbia 
river around the northern side of the lava plateau was obstructed 
by ice streams, which crept down into its valley from the moun- 
tains of the northwest ; the river then rose in a large lake up- 
stream from the barrier thus formed, and the lake found an 
outlet across the lava plains to the southwest. The lake out- 
let persisted long enough to erode a canyon in the lava beds, 
at the head of which its waters plunged down in a group of superb 
cataracts. We shall see their site near Coulee city. 

THE PACIFIC MOUNTAIN SYSTEMS 

The Cascade Range. — West of the Lava plateaus rises the 
Cascade range: a mass of deformed crystalline rocks partly 
covered with lavas, volcanic agglomerates, and tuffs, broadly 
uplifted with warping and faulting and now maturely dissected. 
The range rises to altitudes of 6000 or 8000 feet, and is crowned 
with several huge volcanoes, of which Mt. Rainier is the chief. 



58 THE PACIFIC MOUNTAIN SYSTEMS 

Some observers have thought to recognize, in the prevaiHng 
approach to equahty of summit altitudes, the traces of a pene- 
plain, formed before the upheaval of the range and dissected 
afterwards ; but in the absence of undissected uplands of small 
local rehef at mountain-top altitude this explanation does not 
seem to be completely established. 

The volcanoes that crown the range are all more or less deeply 
dissected; the largest are, beginning on the north near the 
Canadian boundary: Mt. Baker, 10,719 feet, Mt. Rainier, 12,526, 
and Mt. Adams, 12,470, these three being north of the trans- 
verse valley of the Columbia, which separates Washington from 
Oregon ; and Mt. Hood, a dissected cone rising a short distance 
south of the Columbia. In southern Oregon, near the termina- 
tion of the range, a large volcano, once of great height, has lost 
its upper part by engulfment ; and in the huge caldera thus 
formed Kes Crater lake, where we shall camp two nights and 
a day. Lassens peak, a volcanic cone in northern California, 
rises on the boundary between the Cascade range and the Sierra 
Nevada. Many caverns are found in the recent lava flows that 
descend the eastern slope of the mountains in southern Oregon. 

All the higher valley heads of the Cascade range have been 
the seat of local glaciers, which have left their marks in cirques 
and troughs. Of the latter, the most significant is the one 
occupied by Lake Chelan in the eastern slope of the range in 
northern central Washington; the walls of the trough are of 
simple form, the lateral valleys hang above the lake waters, the 
trough bottom is below sea level. These features were first 
recognized and explained by Gannett, in an article that opened 
the modern understanding of the importance of glaciers as 
eroding agencies. 

The Columbia river has cut a deep valley through the Cascade 
range, as if it had had and held an ancient right of way, in ante- 



THE CASCADE RANGE 59 

cedent fashion ; but east of the range the lava plains are covered 
by widespread, continental deposits, beheved to be in large 
part lacustrine and containing an important mammahan fauna ; 
and in so far as these deposits record the temporary obstruction 
of the river and its transformation into a lake upstream from the 
rising mountain barrier, it should not be regarded as a perfect 
example of the antecedent class. Its gorge has been obstructed 
locally by landsHdes, now marked by rapids. We see a narrow 
part of the gorge, known as the Dalles, where the river flows 
between bold walls of lava, the morning before our visit to the 
city of Portland. Another river, the Klamath, much smaller 
than the Columbia, traverses the Cascade range near its southern 
end, in northernmost CaHfornia, and discharges the waters of 
the Klamath lakes from the depressions among the displaced 
fault blocks of southern Oregon. 

The Cascade mountains offer an exceptionally fine example 
of a range that has a wet slope towards the neighboring ocean 
and a dry slope towards the interior. The wet slope bears a 
dense coniferous forest ; the dry slope is nearly or quite treeless. 
During our traverse of the range on the day of our arrival at 
Seattle, we shall see the farthest eastern extension of the forest 
on the ridges north and south of the treeless Yakima valley; 
then as we ascend to the valley head, the forest invades lower 
and lower levels, and after crossing the pass, the whole slope is 
heavily tree-covered. The dry eastern valleys, where they are 
open enough for occupation, are famous for their fruit farms; 
most noted are the Wenatchee and Yakima valleys, in the latter 
of which we shall spend a morning. The western slope of the 
range suppKes a vast amount of lumber ; after felling the trees, 
the labor of clearing away the stumps is a severe preliminary to 
agriculture. The abundant waterfalls of well-fed streams are 
increasingly utilized as sources of electric power. Salmon 



6o THE PACIFIC IMOUNTAIN SYSTEMS 

ascend the streams from the sea every summer in vast numbers; 
a great amount of canned salmon is shipped to eastern markets. 

The Sierra Nevada. — Conceive a mountain mass, composed 
partly of massive granites, partly of compressed and metamor- 
phosed sediments, worn down to moderate or small rehef and then 
overspread with lava streams in its middle and northern part ; 
next raised and tilted as a huge fault block, with its scarp to the 
east and its longer slope to the west, and in this position sub- 
maturely dissected as a whole, and strongly glaciated in its 
higher parts : such seems to be the general quality of the Sierra 
Nevada of Cahfornia. Uncounted quahfications must be added 
before this oversimpHlied scheme can parallel the comphcated 
facts of nature ; yet it serves a useful purpose in affording a frame- 
work on which appropriate details may afterwards be em- 
broidered. 

The general trend of the range is from northwest to southeast ; 
its length is about 500 miles. It begins near the northern border 
of Cahfornia, but fails to reach the southern border by about 
a fifth of the length of the state, of which the southeastern part 
is occupied by members of the Basin ranges. The highest 
summit of the Sierras is Mt. Whitney, nearly 15,000 feet, in the 
southern part of the range near its eastern scarp, where an 
abrupt descent is made to the desert floor of Owens valley. In 
the district of Mt. Whitney the mountainous highland must 
have had a significant reUef, presumably of subdued expression, 
before faulting and uphfting ; it is now a rocky wilderness above 
the tree fine, in which, if one may judge from descriptions by W. 
D. Johnson, Lawson, and Gilbert, glacial erosion seems to have 
reached a late mature stage ; that is, the summit forms have been 
so far encroached upon by the enlargement of valley-head 
cirques, that the sharpened peaks of to-day are only the much- 
reduced remnants of the presumable preglacial domelike forms. 



THE SIERRA NEVADA 



6i 



The upper parts of the preglacial valleys have been converted 
into overdeepened troughs, of which the Yosemite valley is the 
most extreme example ; so extreme indeed that only pronounced 
glacialists hke Gannett and D. W. Johnson regard it as of glacial 
origin. On the eastern side of the range, opposite the Yosemite, 
glaciers of steep descent excavated troughs in the mountain 
slope and deposited large terminal moraines on the desert low- 
land near Mono lake, 
a district that has 
been well described by 
Russell. 

In the region of the 
Yosemite valley and 
farther north, the 
former cycle of erosion 
was more advanced, 
and the worn-down 
mass is only subma- 
turely dissected in the 
present cycle ; that is, 
it presents rolling high- 
lands, here and there 
dominated by isolated residual masses or monadnocks, and in- 
terrupted by sharply incised, narrow-floored valleys. As a whole 
the highlands gradually descend to the west, and at the base of 
the range pass under the broadly aggraded floor of the great 
valley of California. The most elevated eastern parts have been 
glaciated and bear abundant lakelets in small rock basins ; here 
and on the interstream uplands of the western slope, the stream- 
heads have hardly begun the erosion of the present cycle ; but 
they soon descend into sharply cut canyons, of which the greatest 
depth is roughly midway between their heads in the eastern 




Fig. i6. 



Glacial Moraines in the Sierra Nevada, 
California. 



62 THE PACIFIC IMOUNTAIN SYSTEMS 

highlands and their mouths at the western base of the range. 
The tributary streams do not cascade into the main valley after 
the fashion of tributaries which enter troughs of glacial excava- 
tion, but join the larger streams in normally accordant fashion by 
lateral valleys of rapid descent which cut the main valley walls 
down to the main stream. 

The eastern slope of the range in its middle and northern part 
seems to have been produced by compound faulting of sub- 
recent date; basins, more or less aggraded and in at least one 
case holding a fine lake, Tahoe, occupy the depressions in the 
highland thus produced. The eastern base of the range all 
along its length is marked by long fans and slopes of coarse 
waste or " wash," which stretch far into the adjoining de- 
pression. Near the northern end of the range, Pitt river 
cuts across it from the arid basins in the northeastern angle 
of Cahfornia, but no special study has yet been made of its 
canyon. 

Volcanic features are abundant in the central and northern 
part of the Sierra Nevada. The gigantic cone of Mt. Shasta, 
14,350 feet in height, rises at the western base of the range close 
to its northern end, and near the northern boundary of Cah- 
fornia. We shall pass around its western base the day before 
reaching San Francisco. Abundant lava streams cloak the 
western slope of the range ; but the region has been uplifted and 
deep canons have been eroded since the lavas were poured out, 
so that the flows, which presumably followed wide-open valleys 
of a worn-down region, have now assumed the form of table 
mountains. 

While rainfall is abundant all the year round on the Cascade 
range of northern Washington, it is reduced to moderate amount 
and limited to the winter months in southern California, where 
the climate is essentially subtropical, like that of the Medi terra- 



THE COAST RANGES 



63 



nean. Still farther south comes the rainless belt of the trade 
winds, so that the desert of the interior reaches the ocean shore 
in the Mexican peninsula of Lower Cahfornia. The forests 
which clothe all the western slope of the Sierras in the north, 
retreat to its higher parts in the south. The heavy snows of 
the high Sierra justify its second title ; but anything less worthy 
to be called " Nevada " than the state of that name, made up 




Fig. 17, Mount Shasta. 

of desert plains and barren mountains in the Basin range prov- 
ince east of the Sierras, can hardly be imagined. 

The Coast Ranges. — The Olympic mountains in northwestern 
Washington, with altitudes of 6000 or 7000 feet, occupy the 
peninsula between Puget sound and the Pacific ; they appear to 
be a domelike uphft dissected by radial valleys, with exception- 
ally heavy rainfall and dense forests. Thence southward, a com- 
plex of mountains of moderate altitude, maturely dissected or 
subdued and known as the Coast range, extends to the pro- 
nounced " knee " in the shore Hne of southern Cahfornia. 
They are forested in the north, thinly treed or bare in 



64 THE PACIFIC MOUNTAIN SYSTEMS 

the south. Like so many other ranges in various parts of the 
world, and Hke all the mountains thus far mentioned in this 
book — except a few lava-block ridges in southern Oregon — 
the Coast range is no longer in the first cycle of erosion in- 
troduced by the deformation of its rocks. Its northern part 
appears, according to Diller, to be now in the maturity of its 
second cycle, following the uplift which closed a much more 
advanced stage of its first. In some localities the worn-down 
surface of the first cycle seems to descend beneath the modern 
deposits of the valley of California, thus indicating that the 
movement which raised the present range was a warping uplift 
of part of an extensive peneplain, another part of which was 
depressed in the trough of the great valley. Farther south, 
the studies of Lawson indicate repeated dislocations and dis- 
sections in the Coast range belt. The continuation of these 
movements into recent times is shown plainly enough by the 
occurrence of newly raised beaches and lately drowned valleys 
along the Pacific border; and more especially by the displace- 
ment of block on block along a great fault line, recognized as 
such twenty years ago, but made notorious by the slight snap 
which produced the San Francisco earthquake of 1906. 

The Coast ranges are traversed by several rivers, among which 
the Chehalis, Columbia, Umpqua, Rogue, and Klamath deserve 
mention. The Columbia is navigable in its lower course, but 
is obstructed by shoals at its mouth. More important for ocean 
commerce is the channel maintained through the range to the 
north-central coast of Cahfornia by the formerly combined waters 
of the Sacramento and San Joaquin rivers, now drowned by 
recent submergence so as to form the Golden gate and San 
Francisco bay, the most important reentrant south of Puget 
sound on this little embayed coast. We shall have a good view 
of it as well as of the general course of the earthquake fault 



PUGET SOUND AND THE VALLEY OF CALIFORNIA 65 

line during an excursion to Mt. Tamalpais, on our second day 
in San Francisco. 

Puget Sound, Willamette Valley, and the Valley of California. — 

A depression, more or less pronounced, separates the Coast ranges 
from the Cascades and the Sierras. We shall follow it from Seattle 
to Sacramento. Its northern part in northwestern Washing- 
ton is occupied by a branching arm of the sea, known as Puget 
sound, which has at first sight the appearance of being a drowned 
system of normal valleys, but which has been explained very 
differently by Willis, who regards it as occupying the troughs 
maintained by great glaciers which built up the extensive drift 
deposits that inclose it. The disposition of the arms of the 
sound and of several neighboring troughs partly occupied by 
lakes, suggests that the ice at the head (southern part) of the 
sound, advanced southward with somewhat divergent motion. 
Terminal moraines and widespread outwashed gravels — these 
being exceptional in lacking a forest cover — are found on the 
height of land before the transverse valley of the Chehalis river 
is reached. The irregular outhne of Puget sound produces nu- 
merous eddies in the strong tidal currents that swing in and 
out ; and as a result many points of land, or cuspate forelands, 
have been built out from the sHghtly cliffed shore line. The tides 
are peculiar in exhibiting a well-defined diurnal inequality, in 
contrast to those of the Atlantic coast, where successive tides 
are of nearly the same range. 

The Willamette valley of northwestern Oregon contains 
stratified deposits in the lowlands among its hills, which suggest 
its former occupation by a branching water body, possibly an 
arm of the sea. Successive heights of land separate the hilly 
lowlands of the Willamette, Umpqua, Rogue, and Klamath 
valleys. 

The '' valley " or plain of CaHfornia is a remarkably well- 



66 THE PACIFIC MOUNTAIN SYSTEMS 

defined physiographic unit, occupying two thirds of the length 
of its state. Its longer axis measures about 450 miles ; its width, 
about 50 miles. Needless to say, it is in no respects a " valley " 
of erosion, but a heavily aggraded plain, occupying a trough of 
deformation which appears to have been produced by the de- 
pression of part of the extensive worn-down region, the adjoin- 
ing uplifted parts of which are now seen in the Sierra Nevada 
and the Coast range. The valley plain receives many good- 
sized rivers from the sharply incised valleys of the Sierras on the 
east, fewer and smaller ones from the valleys of the Coast range 
on the west. It is drained from the north by the Sacramento, 
of which the apparently antecedent Pitt river forms the head- 
waters ; and from the southeast by the San Joaquin ; it thus 
resembles two plains of the Po, placed together mouth to mouth. 
The broad and gently sloping alluvial fans which extend forward 
from all the valleys of the Sierra are admirably adapted to agri- 
culture, aided by irrigation. Two of the fans in the southern 
part of the alluvial plain raise the surface a little above the 
southernmost part, which therefore holds a marshy water sheet, 
known as Tule lake. 

Settlement of the Pacific Slope. — The Pacific coast was little 
known to the rest of the world in the first half of the nineteenth 
century. The greater part of its length had been settled from 
Mexico, hence the present abundance of Spanish names ; it 
exported hides from Californian ports and furs from farther north. 
Then the discovery of gold-bearing quartz veins and gravels in 
the western slope of the Sierra Nevada made it the goal of an 
adventurous army of invading immigrants from all parts of the 
world. Some made the journey thither by the long, two- 
ocean voyage around Cape Horn ; some crossed the Isthmus of 
Panama between shorter voyages on the Atlantic and Pacific ; 
some dared to make the journey across the continent overland. 



SETTLEMENT OF THE PACIFIC SLOPE 67 

There are now few survivors of those modern Argonauts, the 
original '^ Forty-niners," of CaHfornia, but their children are worth 
meeting, for the tales of danger and hardship that they can repeat, 
as told them by their parents. The feverish years of roving life 
in mining camps have been followed by a more settled life, and 
at present agriculture predominates as the occupation of the 
growing population. The great alluvial valley plain, first oc- 
cupied in its natural condition for cattle raising, then culti- 
vated in wheat fields, now gives its greatest yield from irrigated 
fruit farms. 

Nearly twenty years passed after the discovery of gold be- 
fore the first Pacific railroad was completed across the con- 
tinent, and more than thirty before the Northern Pacific railroad 
reached, the forested shores of Puget sound. Hence the active 
settlement of the F'ar Northwest did not begin until about thirty 
years after the rapid invasion of California, or some thirty years 
ago. Instead of having a population that was largely supplied 
by the initiative of adventurous individuals, among whom men 
were in great majority, the Northwest has been largely settled by 
families, carried quickly by the organized enterprise of railroads 
to terminal cities that were mapped before they were built. 

A third type of settlement is found in the southern part of 
California. There the climate is delectable in its mildness ; but 
rainfall is deficient, and the larger growth of population has been 
delayed until the modern development of irrigation has made 
agriculture and fruit raising highly profitable. As a characteristic 
result, a duty has been enacted by Congress on lemons, whereby 
the crop of southern California can compete to advantage in our 
eastern markets with that of southern Italy, where labor is cheap, 
life is not ambitious, and the expectation of profit is small. 

In recent years engineering enterprise has been actively ap- 
plied to the use of the streams that descend from the mountains. 



68 THE MISSISSIPPI RIVER 

Huge reservoirs have been built in the southern ranges for storage 
of water, to be used in the drier season for irrigation on the pied- 
mont alluvial plains ; where water is not overabundant, it is 
led in cemented ditches to guard against loss by seepage, and 
even in pipes to protect it from evaporation. Streams of rapid 
descent are used to produce electric power, which is transmitted 
astonishing distances to cities on the coast. 

THE MISSISSIPPI RIVER 

The Embayment of the Gulf Coastal Plain. — On our return 
journey we visit an embayment of the Coastal plain of the Gulf 
States, which demands brief description, with especial regard to 
the great river that follows its axis. The embayment is evi- 
dently the result of a down-warping of a preexistent land surface, 
whereby the sea was permitted to advance 500 miles north of 
its present shore line in the Gulf of Mexico. Its waters then and 
their deposits now overspread the depressed area, and thus to-day 
the plateau of southern Missouri and the mountains of central 
Arkansas are separated from Appalachian features of similar 
structure and form in Tennessee and Alabama by a broad re- 
entrant of the southern coastal plain. 

Since the first uphft of this region, the strata of the coastal 
plain have been sufhciently worn away to permit the development 
of a fairly well-defined cuesta, which sweeps northwestward 
across Alabama and Mississippi, and southwestward across 
Arkansas ; but its relief is small, and now, since the latest uplift 
of the region, whereby the youngest coastal borderlands have 
been added to the continent, the cuesta has been maturely dis- 
sected by streams of almost insequent habit, so faint is the dip 
of the cuesta-making strata. The inner lowland, excavated on 
weak, underlying strata, has in Alabama and Mississippi a rich 
black soil, and is famous for its cotton plantations; it is there 



THE MISSISSIPPI RIVER 



69 



that the Negro population frequently exceeds that of the 
Whites. 

The Mississippi River. — It seems probable that the lower 
Mississippi did not exist as the trunk of its upper branches 
before the down- warping of the uplands 
whereby the embayment of the coastal 
plain was foreshadowed ; and at that early 
time, the basin of the upper Mississippi 
very likely drained westward into the sea 
that occupied the site of our Great plains. 
The upHft of great tracts of the continent 
then conspired to turn the drainage of a 
vast land area southward ; and thus the 
lower Mississippi gained its great size. 
The lower river once formed, the last 
uplift of the region caused the immediate 
intrenchment of its valley to a slight 
depth below the uplands of the dissected 
coastal plain on the east and west, the 
rapid broadening of its flood plain to a 
width of from 30 to 50 miles, and the ex- 
tension of its delta in the singular finger- 
like projections, known as '' passes." 

From the head of the embayment, 
marked by the city of Cairo, at the south- 
ern extremity of IlHnois, to the mouth of 
the Mississippi, the direct distance is 560 

miles ; the length of the meandering river is 1060 miles. The 
altitude of the river at Cairo at ordinary stages of flow is 
about 300 feet ; hence the average fall of the river is about 
four inches to a mile, or roughly i : 18,000. The average fall 
of the flood plain is about twice as great as that of the river, 




i«. The Mississippi 
Flood Plain. 



70 THE MISSISSIPPI RIVER 

and the lateral slope of the flood plain away from the river is 
much stronger, being sometimes several feet in a mile. The 
average radius of the Mississippi meanders is from two to 
two and a half miles ; the crescentic lakes of the flaod plain 
represent the maximum dimensions reached by meanders before 
they were cut off and abandoned. Between 1825 and 1897 
fourteen meanders were cut off, and the river would have thereby 
been shortened 160 miles, had it not been for compensation in the 
enlargement of other meanders. The river length therefore 
varies about an average value ; it is always slowly lengthening 
by enlargement of meanders, and it is occasionally and sud- 
denly shortened by cut-offs. 

For thirty years past, engineering works, designed to retard 
or prevent the change of the river course, to improve its channel, 
and to dike the bordering lands against overflow during floods, 
have been in charge of the Mississippi river commission, under 
direction of the Chief of Engineers, U. S. Army, with headquarters 
at St. Louis. Annual reports and elaborate maps have been 
published ; these and the river itself we shall see in a boat trip 
from Memphis, Tenn., where the river swings against the eastern 
border of its flood plain, to Helena, Ark., where it touches the 
western border. 



PART II. DAILY ITINERARY OF THE 
EXCURSION 

First Day, Thursday, August 22 
NEW YORK CITY TO ALBANY AND UTICA 

That division of the city of Greater New York known as the 
Borough of Manhattan occupies the terminal part of the Man- 
hattan prong of the older Appalachian belt, which extends 
south westward from the broad highlands of New England, 
between the sea on the southeast and the sandstone lowland strip 
on the northwest. The end of the prong is low because the 
peneplain, to which the whole region was once reduced, has here 
been little upHfted ; the prong is narrow, because it is over- 
lapped on the southeast by the sea and Hmited on the northwest 
by the near-by lowlands of the red sandstone strip. A short 
terminal portion of the prong is isolated from the rest by a tidal 
water passage, Harlem river and its branch, Spuyten Duyvel 
creek, — names recalling the Dutch settlement of the Hudson, — 
which connects the North or Hudson river on the west with 
East river, this name being given to the narrow water channel 
which joins Long Island sound with New York harbor. 

The deformed crystaUine schists of the Manhattan prong 
are well seen in the excavations now in progress for the con- 
struction of the Grand Central Terminal of the New York Central 
railway lines in the heart of New York city. The rock surface 
is glaciated and occasionally drift covered. 

After starting from the Grand Central Terminal, the train 

71 



72 DAILY ITINERARY OF THE EXCURSION 

soon turns west near Harlem river and along Spuyten Duyvel 
creek to the east bank of the Hudson, which is then followed 
150 miles northward to Albany. The west bank of the Hudson 
is here bordered by the Palisades, a rather even-crested ridge 
maintained on a west-dipping monoclinal sheet of intrusive 
trap, under- and overlaid by weak sandstones; hence the 
Hudson here occupies a subsequent valley, excavated along the 
basal members of the red sandstone strip that is included be- 
tween the Manhattan and Reading prongs of the crystalline 
belt. The gradual ascent of the Palisade crest, for nearly forty 
miles northward from its low emergence southwest of New Y'"ork 
harbor to its termination in a knob known as High Tor, and the 
fair accordance of its growing altitude with that of the neigh- 
boring highlands of disordered crystalline rocks may be taken 
as sufficient evidence of former peneplanation of this district. 

North of the curved end of the Palisade ridge — the curve 
being due to a slight warping of the trap sheet — the Hudson 
widens in Peekskill bay, a natural result of the smaller dip of 
the weak sandstones at the northeast end of their strip than 
along their eastern border. Beyond the end of the red sandstones 
the Hudson, still navigable, occupies a deep and narrow gorge, 
Hmited by the crystalline highlands on both sides and truly 
fiord-like in appearance; its course is at first transverse, then 
longitudinal, then transverse again. West Point, the site of 
the United States Military Academy, occupies a bench on the 
west side of the gorge ; this bench is beHeved to be a remnant of 
an earher valley floor, which is broadly visible in the low upland 
of the Great Appalachian valley, north of the gorge. 

The Hudson here is not a normal river, in the sense that its 
volume depends on the rainfall over its basin, but an estuary 
of brackish water, whose navigable volume is maintained by 
the ocean. Its depth may be due in part to submergence of 



NEW YORK CITY TO ALBANY AND UTICA 



73 



a normal valley, in part to glacial scour of such a valley below 
sea level ; if the latter explanation prove to be correct, the gorge 
of the Hudson might be regarded as a true fiord. 

On leaving the gorge in the resistant crystalline rocks and 
entering obliquely into the folded Appalachian belt, here mostly 
composed of weak slates and flagstones, the older Appalachian 
highlands at once give way to the north-south lowlands of the 
Great Appalachian valley; but in consequence of regional 




Fig. 1 8. The Hudson River, looking North from West Point. 



uplift, the lowlands should now be called uplands, beneath 
which the Hudson has intrenched its narrow course. We stop 
at Fishkill and take an inclined railway to ascend Mt. Beacon, 
a member of the dissected highlands bordering the Hudson 
gorge on the east; here we enjoy an extensive view of the 
gently undulating sky Hne of the highlands to the southwest, 
east, and northeast, of the broad floor of the Great valley to 
the north, west, and southwest, and of its inclosure on the 
farther side by the escarpment of the mountainous Catskill 
plateau. 



74 DAILY ITINERARY OF THE EXCURSION 

On returning to Fishkill and continuing along the Hudson 
to Albany, the tilted flagstones and slates of the Great valley 
are often exposed in railroad cuttings, while the upland surface, 
west of the river, is seen evenly truncating their upturned edges. 
Faint tidal changes of water level are still felt in the Hudson, 
although the water current here is always southward and the 
water soon becomes potable ; numerous ice houses along the 
river bank testify to an important winter industry. Albany, the 
capital of New York state, is at the head of navigation. Here 
we cross the river, and ascend to the surface of a large clay-and- 
sand delta, deposited in the greater Hudson water body (estuary ?) 
of late-glacial time by the inflow of the Mohawk, then tempo- 
rarily a vastly larger river than now, because it brought the dis- 
charge of the Great lakes while the St. Lawrence outlet was still 
blockaded by the retreating Laurentian ice sheet. The Mohawk 
now foUows a northern radius of its ancient delta to the Hudson ; 
it is superposed on rock ledges near its mouth, and near the faUs 
thus produced He the industrial cities of Cohoes and Troy north 
of our route ; at the head of the delta we pass the manufactur- 
ing city of Schenectady. The Helderberg escarpment, one of 
the several steps by which ascent is here made to the mountain- 
ous Catskill plateau, is seen to the southwest of the delta plain ; 
it there turns the corner from facing east into the Hudson vafley 
to facing north into the Mohawk valley. Similar but lower 
escarpments, more or less dissected by obsequent streams, are 
seen on the south as we ascend the Mohawk valley ; the Adiron- 
dacks, which rise gradually some distance to the north, cannot 
be seen because the valley bottom is too deeply incised beneath 
the broad subsequent depression that it follows. 

The value of the tidal and navigable Hudson and the low- 
grade Mohawk valley as a line of travel and transportation from 
the ports of the Atlantic coast to the broad prairies of the in- 



NEW YORK CITY TO ALBANY AND UTICA 



75 



terior, was early perceived. It was by this pathway that 
thousands of early settlers from the Hudson valley and the New 
England States reached the fertile prairie plains, south of the 
Great lakes. The Erie canal, a state enterprise, was con- 
structed in the first quarter of the nineteenth century from the 
head of navigation on the Hudson at Albany through the Mohawk 
valley and beyond to Buffalo at the east end of Lake Erie. It 
is now paralleled through much of its length by two railways: 




Fig. 19. The Mohawk Valley, 



one, the New York Central, which we follow, has four tracks 
from Albany to Buffalo ; the other, the West Shore (so called 
because of following the west shore of the Hudson northward 
from New York city) with two tracks, is seen on the south side 
of the Mohawk valley, while we take the north side from Sche- 
nectady to Little Falls. A new waterway, the Barge canal, 75 
feet wide and 12 feet deep, is now under construction by the 
state for vessels of large tonnage; we see the work in progress 
or lately finished at many points. The traffic along the Mohawk 



76 DAILY ITINERARY OF THE EXCURSION 

may therefore be compared with that which follows the gorge 
of the Rhine. 

The most pecuhar topographical features of the Mohawk 
valley are dependent on the occurrence of transverse faults 
with uphft on the west, whereby the underlying crystalline rocks 
are raised so high that they are now laid bare by erosion. The 
valley is maturely opened on the weaker strata, with a flood 
plain on which the river freely meanders — the breadth of the 
valley floor being, however, more probably the work of the en- 
larged Mohawk in late-glacial time than of the present reduced 
stream — but wherever the river is superposed on the crystal- 
line rocks, the valley is at once reduced to smaller width. The 
uplands maintained on the crystalline rocks are terminated at 
each fault by a well-defined east-facing escarpment, because 
the weaker strata which formerly abutted against the crystal- 
lines are now broadly removed ; hence these scarps should be 
called '' fault-line scarps," as due to erosion acting on a faulted 
mass, and not " fault scarps," a term which should be restricted 
to scarps now more or less dissected, but initially produced 
directly by faulting. Where the first of the stronger fault-line 
scarps is breached by the Mohawk, the bold headlands on either 
side of the valley are known as the '' Noses." A little farther 
west, after the uplifted crystallines have disappeared, a fine 
postglacial gorge has been eroded in the weak overlying shales 
on the south side of the valley, and at its mouth lies the village 
of Canajoharie. Farther on, another fault-line scarp is breached 
by the narrowed Mohawk, which is there beset with ungraded 
rapids ; here the manufacturing city of Little Falls has grown. 
We turn back for a mile on a branch line, to reach the crest of 
the scarp and enjoy a view down the Mohawk valley. Then 
returning to the main line we have a short run up the widening 
valley to Utica, where we spend the night. 



UTICA TO SYRACUSE AND ITHACA 77 

Second Day, Friday, August 23 
UTICA TO SYRACUSE AND ITHACA 

We make an early start from Utica, and soon reach Syracuse. 
The Mohawk valley continues to widen above Utica, and at 
Rome — these being some of the many towns to which classical 
names were inadvisedly applied at a time of hurried baptism 
a century ago — we cross the broad, flat lowland divide between 
the Mohawk-Hudson and the St. Lawrence basins. From this 
point westward the lowland, sloping gently northwest to the 
basin of Lake Ontario, was for a time covered by a great glacial- 
marginal lake, held in when the retreating Laurentian ice sheet 
obstructed the St. Lawrence valley ; it was this lake — to which 
the Indian name, Iroquois, has been given — which received 
the waters of the other Great lakes farther west at the time when 
Niagara falls were initiated, and which suppHed the great volume 
of outflow that flooded the late-glacial Mohawk and built the 
high-level delta by Albany. The shore Hues of the lake, faintly 
developed in the narrow and shallow waters near the outlet, 
become increasingly distinct farther north and west where the 
waters were wider and deeper. 

As we advance farther westward, distant views of the border 
hills of the Adirondacks are obtained to the northeast. Near by 
on the south is the northern margin of the Appalachian plateau, 
sometimes possessing a reHef of 800 or 1000 feet, abundantly 
dissected into spurs and hills by the obsequent valleys of south- 
north streams ; and from this margin the broken country of the 
plateau is continuous for 800 miles southwestward to northern 
Alabama, where we shall cross its southern end on our return 
journey. 

At Syracuse we make a local excursion southeastward into the 
hills of the plateau border, to see two examples of channels and 



78 



DAILY ITINERARY OF THE EXCURSION 



plunge-pool lakes scoured out by the temporary, late-glacial, 
east-flowing Niagarawk river (see p. 21), which took its spas- 
modic course across the plateau spurs, following the variable 
depression defined by the fixed 
northward slope of the plateau 
margin and the shifting 
southward slope of the 
retreating ice sheet, /^l'^' 
The lakes are of 
little impor- 

t a n c e in X^ ^^ ^ , ^ ^ li^/^'^^''""^ '""/y^^^ selves, 

them- A\ n,..A\ : ^vi.■^^> p ' ,— ^-^-^^"""^z but they 

are remark- 
able witnesses to 
extinct conditions of 
drainage, which have 
left many significant marks 
in this district. The origin of 
the channels and lakes was first 
explained by Gilbert; many examples 
occurring in this district have been de- 
scribed by Fairchild. 
On returning to Syracuse and taking our 
train westward, we soon enter the drumhn dis- 
FiG. 20. The trict of central New York, which occupies a part 
Appalachian ^f ^^le confluent Ontario-Erie lowland, here not 

Plateau. . , . ' 

divided by the Niagara escarpment; this feature 
does not make its appearance for some fifty miles farther west. 
The drumlins have been studied by Fairchild, who estimates their 
number at several thousands ; they are more elongated than the 
drumlins of New England ; they are locally parallel to one an- 
other, but as a whole exhibit a slight divergence to the southeast, 




UTICA TO SYRACUSE AND ITHACA 79 

south and southwest ; they completely dominate the topography 
of their district. Roads, property lines, fields, and houses are all 
oriented with respect to the major axes of these elongated hills. 
Xot far north of our route, the drumlins are clift'ed and connected 
by gravel reefs, the work of the waves of the late-glacial Lake 
Iroquois, the outlet of which enlarged the valley of the 
Mohawk. 

The drumHns are interrupted for a short distance by the Monte- 
zuma marshes, which occupy the shallow northward end of the 
trough-like basin of Cayuga lake, to be seen later in the day. 
Beyond the marshes, the old Erie canal, the new Barge canal, 
two steam railways, and a new electric railway all follow 
abandoned waterways eroded through the drumlin belt by late 
members of the glacial-marginal drainage system. 

At Lyons we make a detour southward, in order to see Cayuga 
lake, one of the several Finger lakes, which occupy glacially 
deepened north-south troughs between coarse-textured plateau 
spurs of moderate relief. We turn first south to Geneva ; then 
southeast across a broadly convcA plateau spur, until the trough of 
Cayuga lake comes into sight between this spur and the next 
one on the east. A stop is made at the head of a gorge into 
which a lateral stream plunges in Taghannock falls. A little 
farther on, Ithaca stands on the delta plain at the head (southern 
end) of the lake. We ascend to the grounds of Cornell Uni- 
versity, on the upland of the spur east of the lake trough, for 
the late afternoon hours. The simple form of the smooth spur 
sides and the hanging attitude of many side valleys, from which 
the streams of the upland descend through sharp-cut ravines 
with many falls to the lake, are accepted by most observers 
as indicating strong glacial erosion in shaping the lake basins. 
No valleys of similarly simple form are found farther south, in 
the non-glaciated parts of the Appalachian plateau. During 



8o DAILY ITINERARY OF THE EXCURSION 

the retreat of the ice from the Finger lakes, the local proglacial 
lakes had southward outlets through the plateau country to 
the Susquehanna and other rivers in Pennsylvania. The open 
channels cut through preglacial passes by these temporary but 
vigorous outlet rivers are characteristic features near the Penn- 
sylvania-New York boundary. 

In the evening we take our train, return to Geneva, and go on 
to Rochester. 

Third and Fourth Days, Saturday and Sunday, August 24 and 25 
ROCHESTER TO BUFFALO AND NIAGARA 

Those who rise early may see the falls and gorge of the Genesee 
river, close to the station in Rochester. The falls are upheld 
by the Niagara limestone, which from here westward assumes 
topographic importance and forms at first a low bench, rather 
than a cuesta, separating the Ontario lowland on the north from 
the somewhat higher Erie lowland on the south. Genesee river, 
flowing northward from among the plateau hills across the Erie 
lowland, has cut a gorge several miles in length in the gentle 
slope by which descent is made from the cuesta-bench to Lake 
Ontario. At the head of the gorge, the falls plunge into a 
large amphitheater, around which the city is built on the 
upland. 

The morning run to Buffalo leads across the broad drift- 
covered plain of the Erie lowland ; kames and kettles are passed 
near Batavia ; a gravel-ridge beach of a great proglacial lake 
near Crittenden ; and the plain of the lake bottom is then crossed 
to Buffalo. The gentle ascent to the Appalachian plateau, wliich 
has here lost its strength of expression, is seen some distance 
to the south. 

At Buffalo, we see the harbor on the lake front — the western 



ROCHESTER TO BUFFALO AND NIAGARA 8i 

end of the Erie canal and the eastern end of Lake Erie — • 
and visit the Lackawanna Steel Works ; these are supplied with 
coal brought by rail from western Pennsylvania, and with ore 
from the iron range in northern Minnesota, transported on lake 
boats. At noon our train carries us northward, roughly parallel 
to Niagara river, and we thus reach the city of Niagara Falls, 
where we pass the afternoon and the next day. 



Fig. 21. Niagara Falls. 

During our visit to Niagara, the features that chiefly deserve 
attention are : The rock structure as shown in the walls of the 
gorge below the falls; namely, strong limestones on weaker 
shales and sandstones, all dipping gently southward, and be- 
longing to the great series of strata that form the ancient coastal 
plain in relation to the Laurentian oldland of Canada. The 
broad and nearly level upland of the cuesta maintained by the 
resistant limestones, ending to the north in a well-defined es- 
carpment, beneath which the inner lowland slopes gently to 



82 DAILY ITINERARY OF THE EXCURSION 

the basin of Lake Ontario, visible in the view north from the 
rim of the scarp. The even margin of the escarpment, exceptional 
in normal cuestas of very gently dipping strata, and presumably 
due here to glacial erosion ; the oblique southwestward move- 
ment of the ice sheet seems to have scoured off the normal 
irregularities of the cuesta front. The vast erosion necessary 
to excavate the inner lowland by normal erosion in preglacial 
time, supplemented by glacial erosion. The abandoned beach 
of one of the great proglacial lakes — Iroquois — beneath the 
escarpment on the American side of the lower Niagara river, 
back of Lewiston. The sharply cut gorge, from its beginning 
in the escarpment back to the present falls. The great height 
of the initial falls on the escarpment front. The rapid retreat 
of the falls under the action of a large river, compared to the slow 
retreat of the escarpment and of the gorge walls under the attack 
of the atmosphere. The rapid deepening of the gorge by the 
river, compared to the slow work of small side streams in deepen- 
ing their courses, which hang high over the gorge bottom. Win- 
tergreen flats, on the Canadian (west) side of the gorge below 
the Whirlpool, where the retreating falls were temporarily di- 
vided into a larger American and a smaller Canadian fall — the 
reverse of the condition at Goat island between the present 
smaller American and larger Canadian falls. The Whirlpool, 
where the gorge seems to have been cut back into a drift-filled 
pre- or interglacial obsequent ravine. The narrowing of the 
gorge upstream (south) of the Whirlpool, believed on good 
grounds to be due to the temporary diversion of the waters of 
the upper Great lakes from Lake Huron and Georgian bay direct 
to the lower St. Lawrence river, when the ice sheet had sufh- 
ciently retreated across the province of Ontario and while the 
land was lower to the north ; thus leaving Niagara river to 
be fed for a time only by Lake Erie : had this condition per- 



ROCHESTER TO BUFFALO AND NIAGARA 83 

sisted and the Great lakes outlet served, as it does now, to mark 
the international boundary between the United States and 
Canada, all the fertile agricultural region in the southwestern 
part of what is now the province of Ontario, which closely re- 
sembles western New York state, would have been lost to the 
British provinces. The location of the two railroad bridges at 
the narrowest part of the Niagara gorge. The increase in the 
width of the gorge farther upstream, explained by the return 
of the drainage from the upper lakes to its passage through Lake 
Erie, when the elevation of the land in the northeast raised the 
temporary channel across the province of Ontario to a greater 
altitude than the channel by Detroit; thus the present detour 
of the Great lakes outlet cuts out a part of the Niagara cuesta 
with its adjacent parts of the inner and outer lowlands from the 
United States, and brings this southernmost point of the Do- 
minion of Canada, which so deeply indents the northern boundary 
of the United States, about 300 miles farther south than it would 
otherwise have been. The drowning of the lower Niagara 
to navigable depth in its course from the escarpment across 
the lowland to Lake Ontario, because of the continued rise of 
land to the far northeast. The great plunge pool below the falls, 
where the depth of water is about the same as the height of the 
falls. The small retreat of the American falls compared to the 
rapid retreat of the Canadian falls, the latter being estimated 
to be at present about four feet a year in the central '^ Horse- 
shoe " falls; hence the eventual withdrawal of all the water 
from the American falls, so that Goat island will be a large ex- 
ample of Wintergreen flats. The fine view of the upper rapids, 
the falls, and the gorge from the drift terrace west of the Canadian 
falls. The diversion of water from the river above the falls to 
lateral canals and tunnels for use in developing electric power 
stations, and associated industrial plants. 



84 DAILY ITINERARY OF THE EXCURSION 

Fifth Day, Monday, August 26 
ASHTABULA TO CLEVELAND, TOLEDO, AND DETROIT 

After a night run from Niagara and Buffalo and along the south- 
ern border of Lake Erie, we see in the early morning the lake to 
the north, and to the south the weakening northern margin 
of the Appalachian plateau, which is now losing height pre- 
liminary to its confluence with the drift-covered prairie plains. 
We run near the gently ascending southern border of the Erie 
lowland, between the lake and the plateau margin, which is 
here occupied by a lacustrine coastal plain, in the sense that it 
is covered with stratified clays, the deposit of vanished pro- 
glacial lakes. The plain was laid bare, not by the elevation of 
the land as in the case of marine coastal plains, but by the with- 
drawal of the proglacial lake waters when the northward retreat 
of the ice sheet opened lower and lower lake outlets. Young 
shore lines, formed on the plain during pauses in the with- 
drawal of the lake, may be recognized from the passing 
train. Numerous streams, following consequent courses from 
the plateau, which represents the oldland, across the coastal 
plain to the lake, have eroded narrow valleys of early mature 
form ; the lake waves have cut a cliff, which gives the present 
shore line a much more mature expression than any earlier 
one ; but the plain as a whole remains young and undissected 
back of the cliff and between the valleys. Ashtabula, at 
the mouth of one of the consequent valleys, is an impor- 
tant lake port, receiving iron ore by lake boats from Min- 
nesota and shipping it to Pittsburgh by rail. The significance 
of this port is not especially due to its local advantages, for 
it has no natural harbor, but rather to its lying nearer than 
any other lake port to Pittsburgh. In recent years from 
6,000,000 to 9,000,000 tons of ore have been received here 



ASHTABULA TO CLEVELAND, TOLEDO, AND DETROIT 85 

annually, chiefly for shipment to smelting furnaces in the coal 
fields of western Pennsylvania. 

The plateau on the south gradually disappears and the la- 
custrine plain broadens. One of the numerous consequent 
streams that has eroded a mature valley in the plain is the 
Cuyahoga; at its mouth and on the adjoining plain lies the 
active industrial city of Cleveland. We go on westward across 
the plain to Elyria, to visit a series of abandoned shore lines : 
the highest of them belonged to a local proglacial lake that had 
its outlet southwest of the present Lake Erie to the Ohio river 
(see below) ; the lower ones belonged to Lake Warren, a great 
proglacial water body which had at first an outlet by Chicago 
southwestward to the Mississippi, and later, eastward to the 
Hudson. All of these shore lines ascend a few feet in a mile 
to the northeast, thus indicating a postglacial uphft of the 
continent in that direction. None of the shore lines are of 
nearly so advanced a stage of development as the existing mature 
shore line of the present lake. We see on the way the incised 
meandering valleys of several mature consequent streams. 

On returning to our train and continuing westward we regain 
the outer border of the lacustrine coastal plain. The waters 
of the lake invade some of the valleys, slightly at first, more 
broadly farther on, because of the rise of the land to the northeast 
since the disappearance of the ice sheet. Thus bays are formed 
in the southwestern part of Lake Erie, on two of which are the 
cities of Sandusky and Toledo. Southwestward from the latter 
city, the abandoned shore lines of the highest proglacial lake 
converge to a faint depression in the height of land ; there the 
lake outlet overflowed and cut a shallow channel across the till 
sheet of the prairie plains on its way to the Ohio river. 

At Toledo we take a steamboat to cross the western end of 
Lake Erie and ascend Detroit river to the city of that name, 



S6 DAILY ITINERARY OF THE EXCURSION 

where we spend the evening. The navigable depth of Detroit 
river, a factor of great importance in the shipment of iron ore 
from the northwest and of coal to the northwest, is due, like the 
embayments at Sandusky and Toledo, to the modern rise of the 
land in the northeast, whereby the trench cut in the plain by 
the former river is now drowned. 

Sixth Day, Tuesday, August 27 
MICHIGAN CITY TO CHICAGO 

During the night our route lies across the drift-covered low- 
lands near the southern border of the " lower peninsula " of 
Michigan ; in the early morning we reach Michigan city, at the 
southeastern side of the lake of the same name. This large lake 
once had a greater extension to the south ; but the formation of 
successive sand reefs around its concave southern end and the 
filling of the shallow inclosed lagoons by marshes have somewhat 
reduced its size. Large sand dunes have been formed on the 
reefs, as at Michigan city. 

We follow around the southern end of the lake at a varying 
distance from its shore, and thus approach Chicago. When the 
northward discharge of Lake Michigan was obstructed by ice, 
its outlet ran across the prairies to the southwest, and excavated 
the channel now followed by the Illinois river to the Mississippi. 
The deepening of the channel near the lake was delayed by a 
sill of resistant limestone. When the northward outflow of 
Lake Michigan was established, the divide between the lake and 
the Mississippi system crossed the dry outlet channel near the 
lake. The Indians and the early " voyageurs " there had a 
"portage" for their canoes; there a military outpost. Fort 
Dearborn, was established early in the nineteenth century, and 
there the city of Chicago began its precocious growth. To-day 



MADISON TO LA CROSSE, \VISC. 87 

the channel has been artificially deepened, so as to restore in part 
the ancient outflow, and thus dispose of the sewage of Chicago, 
which was until recently discharged into the lake. This was 
unsanitary, as the water supply of Chicago is taken from the lake 
by a tunnel from beneath a " crib " about a mile from shore. 
The impure waters now turned by the drainage canal into the 
IlKnois river are so far purified by natural processes that St. 
Louis gets an excellent water supply from the Mississippi below 
the mouth of the Ilhnois, as we shall see during our visit to that 
city. Chicago river, enlarged to navigable depth by rise of 
land to the northeast, had become a foul and stagnant water 
channel before the opening of the drainage canal, but is now 
traversed by a gentle current of pure water. 

We spend the day in Chicago, and in the evening take train 
for Madison, Wise. 

Seventh Day, Wednesday, August 28 
MADISON TO LA CROSSE, WISC.i 

We approach Madison in the early morning through the 
drumlin district that occupies much of the area covered by the 
Green bay glacial lobe. At Madison, we visit the grounds of 
the State University, seeing two small Indian mounds on a 
glacial hill, and gaining a general view of the lakes that adjoin 
the city. We then make a local excursion westward across part 
of the glaciated area of the Green bay lobe, first passing two 
recessional moraines and then the terminal moraine, beyond 
which we enter the Driftless area of normal erosional forms, 
here characterized by a maturely dissected bench or cuesta 
formed by a low limestone member of the ancient coastal plain 
series. We return to Madison by another road, farther north, 
and review the same features. 

^ Based on notes by Professor L. Martin, of the University of Wisconsin. 



ss 



DAILY ITINEIL\RY OF THE EXCURSION 



At noon we take train at Madison and run an hour northward 
to Devils lake in Baraboo ridge. This ridge is an ancient rnonad- 
nock of quartzite, which surmounted the peneplain that was !| 
worn down on the fundamental crystalHne rocks previous to the \ 
deposition of the ancient coastal plain strata south of the Lauren- 
tian region. The monadnock was buried in these strata and \ 
thus preserved — a true geographical fossil — for ages, until in 
relatively modern times it was laid bare by the erosion which pro- 
duced the Niagara cuesta and the lowlands of the Great lakes. 




Diagram of Baraboo Ridsre, Wisconsin. 



The western moraine of the Green bay lobe crosses Baraboo 
ridge near the point where we stop ; thus the eastern part of the 
ridge has been ice-scoured, but not the western part. Through 
the middle of the ridge is a deep notch, in which hes Devils lake ; 
we ascend the bluff east of the lake for a general view of the dis- 
trict. On descending to the north, we pass over some of the 
conglomerate beds which Vv^ere formed during the ancient sub- 
mergence of the region, when the ridge was for a time an island. 
On taking the train again, we soon pass the terminal moraine 
and then continue in the Driftless area for the rest of the day. 
Some miles farther on we make a brief stop at Camp Douglas, 
to ascend a sandstone outlier, isolated from the low bench formed 



LA CROSSE, Wise, TO ST. PAUL AND MINNEAPOLIS 89 

by the non-dissected sandstones, farther southwest ; it gives us 
a view over the innermost lowland towards the stripped founda- 
tion of resistant crystalHne rocks which now form the highlands 
of northern Wisconsin. From Camp Douglas we turn west- 
ward, and during the early evening pass another one of the low 
cuestas which partly encircle the Wisconsin highlands, and at 
La Crosse reach the Mississippi river. 

Eighth Day, Thursday, August 29 
LACROSSE, Wise, TO ST. PAUL AND MINNEAPOLIS, MINN. 

In the early morning we follow up the east side of the broad 
channel, incised here through the Driftless area by the enlarged 
Mississippi of late-glacial time, and now occupied by the present, 
normal, underfit Mississippi. We enter the glaciated area be- 
fore reaching Lake Pepin ; there we stop for an ascent of the 
bluffs to the prairie level, whence we obtain a general view of the 
broad channel, and especially of the lower end of Lake Pepin, 
a long expansion of the Mississippi to the whole breadth of the 
channel floor. This singular feature is due to the aggradation 
of the channel floor by the Chippewa, a tributary which comes 
from the northeast and which was at one time so heavily charged 
with waste that its deposits could not be swept away even by 
the Mississippi, and the lake resulted. 

We descend to the train, and follow up the border of Lake 
Pepin to its head, where the misfit Mississippi again wanders on 
the channel floor. Farther on we pass the tributary valley of 
St. Croix river, coming from the north, and here forming the 
boundary between Wisconsin and Minnesota, which has been 
marked by the Mississippi farther south. Here the Mississippi 
has aggraded the channel floor, and a slender lake occupies the 
St. Croix valley. 



90 DAILY ITINERARY OF THE EXCURSION 

St. Paul, the capital of Minnesota, occupies the upland on 
the northeast of the Mississippi, at the head of navigation. 
Here we pass through the city to visit the confluence of the 
Mississippi and the Minnesota at Fort Snelling, a few miles to 
the west. The Minnesota, the smaller river of the two, comes 
from the west and northwest, strikingly underlit, along the 
great channel that was eroded in late-glacial time by River War- 
ren, the outlet of the great proglacial Lake Agassiz. The Missis- 
sippi, the larger river, comes from the north in a gorge of its 
own postglacial erosion, at the head of which, a few miles up- 
stream, are the Falls of St. Anthony, and there the manufactur- 
ing city of MinneapoHs has grown, famous for its flour mills, 
and now the seat of the State University. 

During the erosion of the gorge, the Mississippi was divided 
into two channels, inclosing an island, about midway between 
Fort Snelling and MinneapoHs ; the eastern channel was the 
larger of the two and had cut its gorge back to the point of bi- 
furcation; the waters were then withdrawn from the western 
channel, in which much less progress in gorge cutting had been 
made. A small stream fell into this unfinished gorge from the 
west, and has now cut a httle gorge of its own, at the head of 
which is a small cascade, the Falls of Minnehaha. In the after- 
noon we visit MinneapoHs, and in the evening go on to Duluth. 

Ninth and Tenth Days, Friday and Saturday, August 30 and 31 
DULUTH AND THE IRON DISTRICT OF MINNESOTA 1 

The night ride northeastward from St. Paul carries us across 
the glaciated highland peneplain of east-central Minnesota ; we 
see something of the same country in our ride to-day from Duluth 

^ Based on notes by Professor N. H. Winchell, formerly state geologist of 
Minnesota. 



DULUTH AND THE IRON DISTRICT OF MINNESOTA 91 

northward to Hibbing in the Iron district. This entire region 
is a southwestward extension of the Laurentian highland of 
Canada; it consists of greatly deformed rocks, for the most 
part of crystalHne texture, and has been as a whole reduced to 
moderate relief ; but it is here and there surmounted by subdued 
hills and ridges, standing singly or in groups or ranges ; it has been 
scoured by the Canadian ice sheet, whereby the preglacial in- 
equalities of the surface have probably been decreased in so far 
as the rock hills lost some of their height, and increased in so far 
as shallow basins were excavated in areas of weaker rocks ; abun- 
dant deposits of drift were strewn over the surface either as 
sheets of till or as morainic hills, whereby the preglacial drainage 
of the district was thrown into disorder ; the streams of to-day 
exhibit all the features of a new youth, as they hesitate in count- 
less lakes and swamps where they wander on the drift-covered 
surface, or hasten in rapids and cascades where they are super- 
posed on rock ledges. The short streams that drain into Lake 
Superior have a strong descent in their lower courses, where they 
descend several hundred feet from the slightly dissected highland 
to the lake level. 

After leaving Carlton, about 30 miles west of Duluth, we de- 
scend from the ancient rocks of the highland to a covering of 
lacustrine clays, deposited in a shallow western extension of the 
Lake Superior trough from the waters of a proglacial lake which 
had a southward discharge to the St. Croix river, the junction of 
which with the Mississippi we saw shortly before reaching St. 
Paul. This embayment is now drained by the St. Louis river, 
which comes from the highland on the north, descends by falls 
into the embayment, and then flows eastward to the western 
end of Lake Superior, known as St. Louis bay. We run down 
by easy grade from the highland at altitudes of 1200 feet along 
the clay-covered embayment to the present lake at an altitude 



92 DAILY ITINERARY OF THE EXCURSION 

of 600 feet, and there see that St. Louis bay is inclosed by a huge 
north-south sand reef formed by one of the early proglacial 
lakes, and now standing well above the actual lake surface. We 
follow the southern shore of the bay, thus entering Wisconsin, 
and reach the city of Superior ; there we return into Minnesota 
by following the sand reef to its northern end at Duluth. 

After a short halt we continue our journey, first following 
near the lake shore, then turning inland and ascending the drift- 
covered slope of the highland to the northwest by a strong grade. 
Shore Knes of proglacial lakes have been traced along this slope, 
and all of them show a gradual ascent to the northeast : one of 
the shore lines emerges from beneath the present lake waters a 
few miles east of Duluth ; its concealed part has been drowned 
by the rise of the western lake waters in consequence of the up- 
lift of the continent to the northeast. For the same reason the 
streams that enter the lake hereabouts are all drowned near their 
mouths. Occasional embayments in the rock slope of the high- 
lands, apparently of normal erosional origin yet too large for 
postglacial erosion, suggest that the deep basin of Lake Superior 
is of preglacial origin ; it has been explained by down faulting, 
but without full demonstration as yet. 

After the ascent from the lake margin, we cross the highlands 
over heavy and abundant drift deposits with many lakelets and 
swamps, which cover the rock surface over large areas. We 
thus reach a belt of country named the Mesabi iron range from 
its ore deposits, not from its relief, for it is gently undulating ; 
farther on is the Giants range, a belt of granitic hills that rise 
several hundred feet over the highland ; and back of this is the 
VermilKon iron range. We cross the headwaters of St. Louis 
river on the way. At Hibbing we visit two of the mines ; the 
ore being *' soft," it is excavated by steam shovels from huge 
open pits. The extensive development of the mines in the last 



DETROIT, MINN., TO BISMARCK, N.D., AND BEYOND 93 

25 years has attracted a large population into a wilderness that 
otherwise has very Kmited resources. The wholesale working 
and enormous dimensions of the ore pits in the highland and the 
ingenious devices for rapid shipment of ore at Duluth deserve 
attention. Return to Duluth is made in the late afternoon and 
early evening. 

On Saturday morning we are invited to make an excursion 
from Duluth by steamboat across St. Louis bay to Fond du Lac 
and a new steel plant. In the afternoon we see something of 
Duluth, a significant feature being a boulevard that follows an 
ancient lake shore line on the slope of the highland northwest 
of the present lake and 650 feet above its waters. In the late 
afternoon, we resume our journey by train, returning past 
Superior and Carlton, thence continuing westward across the 
highland, and crossing the upper Mississippi at Brainerd in 
central Minnesota late in the evening. 

Eleventh Day, Sunday. September i 
DETROIT, MINN., TO BISMARCK, N.D., AND BEYOND 1 

During the night we have crossed the drift-covered highland 
peneplain of north-central Minnesota, and in the early morning 
find ourselves on the eastern border of the treeless Great plains, 
where weak stratified deposits, dipping very gently to the west, 
lap upon the slanting highland floor of the resistant crystalline 
rocks. We descend into the so-called Red river valley, a broad 
subsequent depression, here about 40 miles wide, which has been 
eroded on weak basal strata, between the crystalline highlands 
on the east and a gentle rise of stronger strata on the west, known 
as the Manitoba escarpment. The valley is now covered with 
a smooth sheet of till, made yet smoother by a cover of silts de- 

^ Based on notes by Professor H. E. Simpson, University of North Dakota. 



94 DAILY ITINERARY OF THE EXCURSION 

posited from the waters of the great proglacial Lake Agassiz, 
of which we saw the outlet trench at Fort Snelling, near St. Paul. 
The highest eastern beach of the lake is passed near Muskoda. 
We descend by a long, straight track on an embankment, from 
which extensive views are offered to the north and south. The 
Red river, a typical young consequent stream, flows northward 
through the axis of the valley plain in a narrow, intrenched 
meandering valley of small depth. Consequent tributaries 
are seen on the east and west in Buffalo and Cheyenne rivers. 
Vast stretches of the plain are undissected ; here the water often 
Kngers doubtfully after thaws and heavy rains, undecided as to 
the direction of run-off. 

At Red river crossing we pass the competitive cities of Moor- 
head, Minn., and Fargo, N.D., in the quiet of Sunday morning. 
The fertility of the lacustrine silts has made the valley a wheat- 
growing region : property is often held in vast farms comprising 
thousands of acres; farming is done in a wholesale manner; 
the sale of agricultural machinery is an important preparatory in- 
dustry. Beyond Casselton and Wheatland, in the western half 
of the plain, we pass several abandoned shore Hnes, and then 
ascend the slope of the Manitoba escarpment; but the ascent 
is so gradual that our track is still straight. The escarpment 
extends far northward into Canada, with increasing rehef; to 
the south it weakens and is known as the Coteau des Prairies. 

After ascending the scarp, we cross a broad, drift-covered up- 
land of gradually increasing height. Irregular moraines mark 
pauses in the retreat of the ice sheet from its greatest advance 
many miles farther southwest on the Great plains. Large 
channels, occupied by underfit streams, represent the work of 
late-glacial rivers, fed from the retreating ice sheet. The' first 
one of these, drained by Cheyenne river, we cross on a superb 
viaduct, and look down on Valley city on the channel floor. A 



IN THE BAD LANDS OF THE LITTLE MISSOURI 95 

few miles east of this channel a low cuesta, with ragged front and 
outliers, is determined by the outcrop of more resistant strata 
on the peneplain to which this whole region was reduced in pre- 
glacial times. Other channels little farther west have been 
obstructed by later morainic deposits, and now hold long lakes 
or strings of lakes ; we cross the middle of Eckelson lake, the 
longest of the group. Farther on is another channel, drained 
by James river, and occupied on our hne by Jamestown, to and 
from which we descend and ascend on our westward course. Some 
ten miles west of Jamestown, we cross the strongest escarpment 
of the region, the Coteau du Missouri ; then we descend by an 
open depression to the broad valley of the Missouri river at 
Bismarck, the capital of North Dakota. It is noteworthy that 
the uplands on either side are here much more elaborately dis- 
sected than was the case with the uplands bordering the trench 
followed by Cheyenne river. 

After crossing the Missouri, we follow the lateral valley of 
Heart river westward, and gradually reach the upland peneplain. 
Glacial drift is here inconspicuous as a topographic element. 
Occasional residual hills attest the erosional origin of the plain, 
which we traverse until nightfall. 

Twelfth Day, Monday, September 2 
IN THE BAD LANDS OF THE LITTLE MISSOURI 

The morning finds us on the Great plains, which are becoming 
more and more arid. On approaching the north-flowing Little 
Missouri, the upland peneplain of the former cycle of erosion 
becomes more dissected, and we soon descend into the valley of 
the present cycle at Medora. We here make an all-day wagon 
trip, during which a large variety of characteristic bad-land 
features will be seen, including ragged escarpments that sur- 



96 DAILY ITINERARY OF THE EXCURSION 

mount the peneplain of the region, and minutely dissected valley 
sides that are intrenched below it ; we visit a cattle ranch in 
the afternoon. Towards evening we return to Medora and 
take our train westward, ascending from the valley and again 
traversing the Great plains after dark. 

Thirteenth Day. Tuesday, September 3 
LIVINGSTON, MONT., TO THE YELLOWSTONE NATIONAL PARK 

During the night the railroad reached the valley of the Yellow- 
stone, into which it has descended from the plains. The dis- 
sected valley sides give abundant exposures of the nearly hori- 
zontal strata of the region, little covered with vegetation. As 
we approach Livingston, the maturely dissected Crazy moun- 
tains may be seen to the north; they are composed of essentially 
horizontal strata of the plains series, traversed by numerous 
dikes, to which their survival is due. They indicate in the most 
striking manner the enormous erosion accomplished in the gen- 
eral peneplanation of the neighboring Great plains region. 

At Livingston we turn south, and soon enter the lower canyon 
of the Yellowstone, where it has trenched the hard, upturned 
rocks of the Rocky mountain front, which here has a local turn 
from east to west. The most important mountain-making strata 
here are heavy and resistant limestones, dipping to the north. 
Their attitude gives the impression that the altitude of the 
mountains above the neighboring plains is due to upheaval : as 
a matter of fact, the excess of altitude is due to their hardness, 
which has enabled them, except where trenched by streams and 
rivers, to preserve a large measure of the elevation gained by 
regional uphf t after the whole region had been subdued ; while 
the neighboring weaker strata have lost their elevation in re- 
duction to the vast peneplain of the Great plains. This illus- 



LIVINGSTON TO THE YELLOWSTONE NATIONAL PARK 97 

trates the difference between ''age" and "stage"; the steep- 
walled canyon cut by the Yellowstone in the hard limestones is 
of the same age, measured in years, as the peneplain, which has 
been worn down by general weathering and washing on the weak 
strata of the plains; but the canyon is still in an early stage of 
its cycle of erosion, while the plains are in a late stage of theirs : 
the canyon is in a young stage, while the plains are in an old 
stage of development, although they are of essentially the 
same age. The distinction here made was concisely stated by 
Kant, who wrote : ''Wenn man wissen will, ob ein Ding alt, ob es 
sehr alt, oder noch Jung zu nennen ist, muss man es nicht nach 
der Anzahl der Jahre schatzen die es gedauert hat, sondern nach 
dem Verhaltnis, dass diese zu derjenigen Zeit gehabt haben, 
die es dauern sollte." 

Upstream (southwest) from the canyon the valley broadens, 
as if the rocks were less resistant; but its breadth is possibly 
due to down faulting. The latest lava flows in the district are 
seen in the valley, 15 or 20 miles above the canyon. No detailed 
physiographic account has yet been prepared of the adjoining 
mountains ; but the topographic map strongly suggests the 
occurrence of an uplifted and dissected peneplain, its highlands 
standing at altitudes of about 10,000 feet. This inferred pene- 
plain must truncate the upturned strata of the mountain front ; 
hence it seems necessary, as above implied, to regard these moun- 
tains as belonging in the growing class of two-cycle forms ; the 
first cycle, introduced by strong deformation, having reached old 
age before the second cycle was introduced by widespread elevation 
with more or less warping and faulting. Thirty miles above 
the canyon, the valley turns to the southeast and narrows, thus 
continuing 17 miles to the railroad terminus at Gardiner. Here 
we take stage to Mammoth hot springs in the Y^ellowstcne 
national park. 



98 DAILY ITINERARY OF THE EXCURSION 

Fourteenth to Eighteenth Days, Tuesday to Sunday, September 3 to 8 
IN THE YELLOWSTONE NATIONAL PARK 

A description of the Yellowstone national park, where we 
stay until our nineteenth day, is provided in the pamphlet issued 
by the Department of the Interior, of which a number of copies 
will be placed at the disposal of our Excursion party. 

Nineteenth Day, Monday, September 9 
YELLOWSTONE NATIONAL PARK TO BOZEMAN, MONT. 

We make an early start from the Canyon hotel, return to 
Mammoth hot springs, and then by stage and train to Gardiner 
and Livingston. There our westward journey is resumed on 
the main line of the Northern Pacific railway. The Rocky 
mountain front, which south of Livingston makes a turn to the 
west, soon takes its prevailing northward course again, sharp 
folding and faulting occurring in the reentrant thus formed. Its 
northward continuation forms the Bridger range, in which the 
mountain-making Hmestones stand about vertical and produce 
a rather narrow and serrate crest. The strata of the plains are 
sharply upturned and greatly worn down in subdued forms for 
several miles east of the range ; to the west the resistant crys- 
talline mass of the mountain foundation sinks into the Boze- 
man basin, an excellent example of an aggraded intermont basin 
produced by the warping w^hich introduced the second cycle 
of erosion in the Rocky mountain system. We ascend a sub- 
sequent valley west of Livingston to a tunnel beneath Bozeman 
pass in the foothills of disturbed plains strata; then descend 
westward to the basin through a canyon in the upturned 
Hmestones ; so that the mountain front is here drained by a 
stream, Meadow creek, which flows against the uplift of the 



BUTTE, MONT., TO SPOKANE, WASH. 99 

strata : it is probably consequent on the warping of the second 
cycle. 

The broad Bozeman basin is drained by Gallatin river, which 
with Madison and Jefferson rivers form the three headwaters of the 
Missouri. The Gallatin has eroded a broad floor beneath the 
bench land of the earher basin deposits. At the northern side 
of the basin, where the three rivers unite in the north-flowing 
Missouri, the strongly folded mountain-making limestones and 
associated strata are reduced to small rehef, and together with 
the resistant crystaUine mass of their foundation, all of which 
elsewhere rise in mountain crests, descend beneath the horizontal 
deposits which cover the basin floor, a behavior that is highly 
characteristic of a two-cycle mountain system. Some distance 
to the north, the Missouri, after traversing other basins, makes 
its escape to the plains by a deep and narrow gorge in the Front 
range. 

Twentieth Day, Tuesday, September 10 

BUTTE, MONT., TO SPOKANE, WASH. 1 

In the early morning we cross the continental divide between 
a branch of Jefferson river, which belongs to the Missouri-Missis- 
sippi system, and Deerlodge river, which belongs to the Columbia 
system. The divide is here formed by the crest of what seems 
to be a tilted block of granite, which had been reduced to low 
relief in the previous cycle of erosion, and which now, after up- 
lift so as to present a long slope to the east and an abrupt fault 
scarp to the west, is submaturely dissected in the present cycle. 
We ascend the long eastern slope by many curves, and descend 
the western scarp by sidling along it to the north. The descent 
leads us to the city of Butte, famous for its copper mines; here 
we make a brief stop. 

^Including notes by O. E. Hershey, of Kellogg, Idaho. 



lOO DAILY ITINERARY OF THE EXCURSION 

On resuming our journey, we follow the valleys of Deerlodge, 
Hellgate, and Missoula rivers in a generally northwestward 
direction, through a region for which no detailed physiographic 
accounts have yet been pubHshed. The valley is at first open ; 
below Drummond, it narrows ; at Missoula it opens again, and 
here it has been occupied by a late-glacial lake, the shadowy shore 
Hues of which are seen at many levels on the mountain slopes 
southeast and east of the city. At Missoula, Bitterroot river 
comes from a broad " valley " or intermont depression on the 
south, which, like many other depressions hereabouts, seems to be 
more the product of deformation than of erosion; it is inclosed 
by a subdued range on the east, and by the more Alpine Bitter- 
root range on the west, which here divides Montana from Idaho. 
This range appears to be a maturely dissected fault block; its 
valley heads were glaciated, its peaks were sapped and sharpened 
by the excavation of cirques, and large moraines were deposited 
forward from the overdeepened trough mouths in the broad 
valley at the eastern mountain base. The Bitterroot valley 
has been much aggraded by waste, chiefly from the higher range 
on the west ; it is celebrated for its apple farms on the irrigated 
" bench land " of early glacial deposits, below which the river 
has eroded a mature pathway in the valley filling. 

We follow the Missoula valley through a mountainous region, 
in which forest fires have caused terrible loss of timber, the 
great fire of 1910 having been especially destructive in this 
district. In the late afternoon we leave Montana and enter 
Idaho ; we then pass around the northern border of Lake Pend 
d'Oreille, the origin of which, like that of Lake Coeur d'Alene 
farther south, is presumably associated in some way with glacial 
action. We then cross the western outlet arm of the lake, and 
run southwestward to Spokane, on the western border of the 
mountains, in the early evening. 



SPOKANE TO COULEE CITY, WASH. loi 

Twenty-first Day, Wednesday, September 1 1 
SPOKANE TO COULEE CITY, WASH. 

Our train leaves Spokane about midnight and carries us across 
the treeless lava plateau country, on which the morning opens. 
The surface is rolling ; it is here to be regarded as in great part 
a peneplain produced by long-continued erosion of a deformed 
surface ; for the lava flows, usually horizontal, are here and there 
interrupted by strong monoclinal flexures, which are now re- 
duced to a small residual of their initial relief. The region is 
subarid ; dry farming is practiced here, as there is no water now 
available for irrigation over a large part of the plateau. x'Vt 
Coulee city we make local excursions in the morning and after- 
noon : in the morning a short distance northeast to see a re- 
duced monoclinal flexure, across which the upper course of the 
Columbia river, temporarily diverted to this path by glacial 
obstruction of its northwestern '' big bend," cut a well-graded 
channel or "coulee"; in the afternoon a short distance south- 
west to see the lower course of the same temporary river, where 
it has eroded a canyon in horizontal lava beds ; the head of the 
canyon was the site of a superb cataract of complicated form ; 
beneath the cliffs at the head of the canyon, small plunge-pool 
lakes remain, which remind us of the Green lakes of similar ori- 
gin which we saw on our second day, near Syracuse, N.Y. Sev- 
eral Hnear lakes occur farther down the canyon, probably due to 
the irregular aggradation of its floor by lateral in wash. Moses 
coulee, in the lava plains some twelve miles to the northwest, 
may be similar in origin to Grand coulee, cut at a lower level 
and later date. 

In the late afternoon we take our train again and turn south- 
ward across the lava plateau, and in the night cross the Columbia 
river at Pasco. 



I02 DAILY ITINERARY OF THE EXCURSION 

Twenty-second and third Days, Thursday and Friday, Sept. 12 and 13 
NORTH YAKIMA TO SEATTLE, WASH.i 

From Pasco on the Columbia river our route turns northwest 
up the valley of Yakima river, through the westernmost part of 
the lava plateau and into the eastern slope of the Cascade range. 
The plateau structure is here complicated by a series of low 
anticlinal uplifts with east-west axes, formed after the peneplana- 
tion of the region. The Yakima has cut young gorges through the 
uplifts and aggraded the intervening depressions. Some of the 
monoclinal margins of the uplifts have suffered from recent land- 
slides on their flanks ; a good example is seen south of the rail- 
way shortly before reaching Topinish station. North Yakima lies 
in one of the aggraded depressions, in the center of an important 
district of irrigated fruit farms, which we visit in the morning. 

In the afternoon we continue to ascend the Yakima, crossing 
several aggraded plains which occupy the depressions, and pass- 
ing through several gorges eroded in the uplifts; we follow one 
of the finest of the latter with a pronouncedly meandering course 
just before we reach the largest of the former, in which Ellens- 
burg is the chief town. The highlands to the north and south 
of this basin bear the easternmost extension of forests ; the lower 
ground is still treeless, except for orchards of fruit trees and for 
lines of poplars which serve as windbreaks. Rainfall increases 
with altitude, from 6 inches near the Columbia river, to 80 or 
100 inches near the summit of the Cascades. The forest descends 
into the valley before the valley head is reached ; thereafter the 
whole region except the higher summits is tree-covered, partic- 
ularly on the western slope, where the forest growth is very 
dense. The Y^akima heads in three glacial lakes north of our 
route ; the divide is crossed in a tunnel at an altitude of 2850 

^ Based on notes by Professor E. J. Saunders, of the University of Washington. 



NORTH YAKIMA TO SEATTLE, WASH. 



103 



feet. The western valleys are much aggraded with glacial drift ; 
we follow them down to the open country near Puget sound, 
and reach its shores at Seattle in the evening. 

Our twenty-third day is spent in this vigorous young city, 
which is connected with the East by three competing railway 




Fig. 23. Valley of Yakima River, Washington. 

lines, and which has in recent years grown to be the chief port 
of the Northwest for traffic with Alaska. The local topography 
being unfavorable to civic growth, an enormous work of grad- 
ing has recently been undertaken. The State University is 
within the city hmits on the north. 



I04 DAILY ITINERARY OF THE EXCURSION 

Twenty-fourth Day, Saturday, September 14 
SEATTLE TO TACOMA, WASH.. AND SOUTHWARD 

We go by boat up the sound (southward) from Seattle to 
Tacoma ; the railway between these two cities follows an ag- 
graded trough a little farther east. The shore line is but Httle 
changed by wave action from its initial form. Point Pully, 
about midway on the eastern shore, is a good example of the 
cuspate forelands which have been frequently built out by eddy- 
ing tidal currents; deltas occupy the heads of sea arms into 
which good-sized streams flow. Mt. Rainier rises in the south- 
east ; the Olympic mountains in the west. We spend the after- 
noon in Tacoma, and go on southward in the evening, passing 
Portland about midnight and turning eastward up the Columbia 
river. 

Twenty-fifth Day, Sunday, September 15 

THE DALLES TO PORTLAND, ORE., AND SOUTHWARD 

The early morning finds us at the Dalles in the Cascade range, 
where the Columbia has cut a gorge through heavy beds of 
columnar lava. We follow the river downstream in the fore- 
noon, and spend the afternoon in Portland. In the evening, 
we continue our journey from Portland southward up the 
Willamette valley; we pass through the Umpqua valley in the 
night, and enter the Rogue river valley early the next morning. 

Twenty-sixth, seventh, and eighth Days, Monday to Wednesday, 
September 16 to 18 

FROM MEDFORD, PAST CRATER LAKE, TO KLAMATH FALLS 1 

The morning of September 16 opens at Medford, where 
we see abundant fruit farms, and whence we go in automobiles 

I Based on notes by J. S. Diller, U. S. Geological Survey. 



FROM MEDFORD TO KLAMATH FALLS 105 

up the valley of Rogue river to the northeast. The Klamath 
mountains on the west consist of ancient crystalline rocks, from 
which a great series of younger strata dip under the heavy lava 
flows which here form the Cascade range on the east. As we 
ascend into the latter, newer lava streams and tuff deposits are 
seen filling valleys cut in the earlier lavas. The upper valley 
of Rogue river has been invaded by a flow in which the river is 
now working. 

The shghtly serrated volcanic rim which incloses Crater lake 
finally rises ahead of us ; the volcanic plug of Union peak rises 
on the southeast; we ascend to the southwestern side of the 
rim and there spend two nights and the day between them. The 
lake with a district around it was made a national park in 1902. 
The altitude of the volcanic rim is from 70C0 to 8000 feet ; its 
diameter, five miles ; the level of the lake is 6177 feet ; its depth, 
nearly 2000 feet. The ancient volcano, named Mt. Mazama, 
probably rose to 14,000 feet ; its flanks were deeply ravined ; 
the huge cavity of to-day appears to have been formed by en- 
gulfment rather than by explosion, because no great quantity 
of the products of explosion are found on the lower slopes ; 
the engulfment took place after the dissection of the volcano, 
for the cliffs of the cavity now truncate well-formed radial 
valleys, the heads of which must once have been much higher 
than the present rim ; the engulfment took place after glacial 
action had enlarged some of the valleys, for glaciated rocks are 
found in the present valley heads, as if glaciers had extended 
down into them from some higher source, now vanished. Wizard 
island is a young volcanic cone formed in the lake after en- 
gulfment. 

On the morning of September 18 we take automobiles to 
descend southward to the town of Klamath Falls, at the eastern 
base of the Cascade range. We follow the road of our ascent 



io6 DAILY ITINERARY OF THE EXCURSION 

for a few miles and then turn southeastward down the valley 
of Anna creek, which has cut a sharp gorge beneath an earher 
valley floor. The volcanic plug of Union peak is now seen to 
the west; a fault scarp and large springs are passed on the way 
down. 

Several extensive water bodies, the Klamath lakes, are held 
at the eastern base of the mountains by lava sills. The town 
of Klamath Falls lies between the upper and lower lakes, on the 
east side of the river that connects them. Great irrigation works 
are in progress in this district. Our train meets us here, and in 
the afternoon we run southwestward down a branch railroad 
following Klamath river through the Cascade range to the main 
line at Weed in northern California ; then going on southward 
we pass the western slope of Mt. Shasta in the late afternoon. 
An aggraded basin occupies a depression north of this great 
volcano ; it is drained to the Klamath river, which escapes 
through the Coast range on the west to the Pacific. The ter- 
minal moraine of the Whitney glacier may be seen high in the 
northern slope of Shasta; several subordinate volcanic cones 
and knobs rise hereabouts. The railway line crosses a col at the 
west base of the huge volcanic cone, and we thus pass from 
Klamath river drainage to the head of the Sacramento river. 
South of Sisson, the line crosses a lava field and enters the canyon 
of the Sacramento, which it then follows; remnants of lava 
flows are seen clinging to the canyon walls for many miles. 

Twenty-ninth Day, Thursday, September 19 
REDDING TO SAN FRANCISCO 

We enter the northern end of the valley plain of Cahfornia 
at Redding in the night and follow it southward through the 
morning. The Marysville buttes, a group of dissected vol- 



SAN FRANCISCO AND LOCAL EXCURSIONS 107 

canic hills rising in the plain, are passed on the way. The Sacra- 
mento and its tributaries wander over the plain, which they 
are aggrading, all the more actively since the auriferous gravel 
beds along the western flanks of the Sierra Nevada have been 
extensively washed by the hydraulic method of gold working; 
the addition of detritus to the lower streams has increased their 
load so greatly as to cause them to spread sand and gravel far and 
wide, thus devastating parts of the plain and giving rise to Htiga- 
tion between the agricultural and the mining interests. Detailed 
maps have been made of this district, to serve as the basis of 
official investigation of means by which the devastation of the 
plain can be diminished, and its reclamation effected. 

We follow the plain southward to the great marshes of Suisun 
bay, the innermost expansion of the embayment formed by 
the depression and drowning of the " Golden Gate." We then 
approach the eastern base of the Coast ranges, where they con- 
strict the embayment into a narrow passage, known as Kar- 
quines strait, which we follow westward, and thus reach an inter- 
mediate expansion of the drowned district, known as San Pablo 
bay on the north, and San Francisco bay on the south. We turn 
south from Karquines strait, cross a lowland that connects the 
San Pablo peninsula with the ridges in the east, pass Berkeley, 
the seat of the State University, and thus reach Oakland, where 
we ferry across the bay to San Francisco. 

Thirtieth and Thirty-first Days, Friday and Saturday, September 20 

and 21 

SAN FRANCISCO AND LOCAL EXCURSIONS 

We are invited to an all-day excursion on September 20 to 
Mt. Tamalpais, which is reached by crossing the bay to the north 
and ascending by an inclined railroad to the summit. A grand 



io8 DAILY ITINERARY OF THE EXCURSION 

view is spread before us, embracing the ridges of the Coast range, 
the irregular embayment of the ocean, and the ocean itself. 

September 21 will be given to several local excursions, as 
selected by the members of the party. In the afternoon we visit 
the University of California in Berkeley, and take train in the 
evening, to begin our eastward journey. 

Thirty-second Day, Sunday, September 22 1 
ACROSS THE SIERRA NEV.ADA TO THE BASIN R.\NGE PROVINCE 

We have ascended the lower western slope of the Sierra Nevada 
during the night by a winding route on the slanting highland be- 
tween the young valleys of Bear river on the north and of the 
North fork of American river on the south. The morning 
opens on the highlands, which are surmounted by monadnocks 
and dissected by deep canyons. We may have an early view 
from Cape Horn, a spur of the highland which projects south- 
ward over the canyon of the North fork of American river. On 
reaching the head of Bear river, we cross the highland to the 
south side of the canyon of the South fork of Y^iba river, which 
we follow eastward. Monument hill is a strong monadnock 
on the south; Signal peak is another to the northeast; many 
glacial lakelets occur on the highlands to the north. 

Towards the head of the South fork of Y^uba river, its valley 
becomes open and shallow, as if it were here Httle changed from 
the form gained in the earHer cycle, before the uplift and tilting of 
the Sierra mass. Monadnocks rise around us ; signs of glacia- 
tion are abundant; the forests have been ruthlessly cut away. 
We tunnel through the crest of the range under Donner pass 
(7000 ft.), then loop around the eastern spurs, descending rapidly, 
passing Donner lake, and thus reach Truckee river, the out- 

1 Including notes by Henry Gannett, U. S. Geological Survey. 



ACROSS THE SIERRA NEVADA 109 

let of Lake Tahoe, a beautiful sheet of water which occupies 
a depression between fault blocks some ten miles to the south. 
We continue to descend through the winding canyon of Truckee 
river and thus enter the Basin range province. The first inter- 
mont basin is known as Truckee meadows, in which Reno is 
a considerable city for an arid region ; Carson city, the capital 
of the state of Nevada, and Virginia city, formerly more famous 
than now for its gold and silver mines on the Comstock lode, 
lie to the south of our line. Prize fights are permitted and divorce 
is faciUtated in this desert state, as if to add to its attractions. 

East of the Reno basin, the Truckee enters a canyon through 
unnamed mountains, and thus reaches a larger basin in which 
Wadsworth is the chief town ; here is the beginning of the Lake 
Lahontan area in which we run for a long distance. The river 
turns northward to Pyramid lake, which occupies a depression 
between two meridional ranges. Our route passes around the 
southern end of the Natchez range ; then we run northeast- 
ward across barren alkali flats, the dust from which fre- 
quently adds much discomfort to travel ; dust whirls and 
mirages are often noted ; thus we approach Humboldt river, 
which comes from the northeast and turns southward to reach 
Carson lake on an extensive intermont plain. The Humboldt 
river is followed between the Trinity mountains on the northwest 
and the West Humboldt range on the southeast; a fault has 
been traced along the nearer base of the latter, and the range is 
therefore believed to be a dissected fault block. We stop in the 
depression between these two ranges, to examine a series of shore 
ridges formed by the currents and waves of Lake Lahontan ; they 
are so arranged as to indicate many pauses during a long period 
of rising waters, followed by a rapid disappearance of the lake. 
We go on up the Humboldt river, still following the bed of 
the ancient lake, to Winnenmucca and beyond in the evening. 



no DAILY ITINERARY OF THE EXCURSION 

Thirty-third Day, Monday, September 23 
ACROSS GREAT SALT LAKE TO OGDEN AND SALT LAKE CITY 

We enter the area of Lake Bonneville by a gap in the Gosiute 
range, continue across the lake-bottom plain, and cross the 
northern part of Great Salt lake, a very shallow sheet of water, 
by a long embankment, which was recently constructed with 
much difficulty, to avoid the long detour of the original route 
north of the lake. We pass Terrace, Lakeside, and Promontory 
ranges, which were all islands in Lake Bonneville, the shore lines 
of which are traced all around their flanks at various levels. 
We thus reach Ogden, near the base of the Wasatch range, 
which limits the Basin range province in the east. 

The most significant features to be observed while we are in 
the Basin range province are : The generally well-dissected 
and subdued forms, in which the structure is commonly con- 
cealed under a graded cloak of creeping waste. The occasional 
outcrop of rock ledges, in which the structure of the mass is 
all the more clearly shown by reason of the scantiness of vegeta- 
tion. The prevailing indifference of the base line of a range to 
its lines of structure, thus indicating, if the slope is steep and the 
base line simple, that the range there exhibits a dissected fault 
scarp ; or if the slope is gentle, that it there exhibits the inclined 
back of a tilted block, which had already been reduced to moderate 
or small relief before block faulting took place. The occasional 
occurrence of triangular facets, sometimes well defined, more 
commonly rounded and blurred by weathering, by which the 
mountain spurs are truncated along the simple base line of a 
dissected fault scarp ; on the other hand, the occasionally vague 
ending of low, sprawling spurs and hills, which merge irregu- 
larly and indefinitely with the aggraded intermont plains, thus 
giving the impression that they are the last remnants of a worn- 



ACROSS GREAT SALT LAKE TO OGDEN m 

out mountain system, not refreshed by renewed elevation. 
The long slopes or fans of waste, heading in each ravine of a 
mountain side and spreading forward with gradually decreasing 
slope far into the intermont depressions ; the coarse texture 
of the waste near the apex of the fans, where exceptional floods 
from the mountains have swept out great bowlders; and the 
flat floor of the central depressions, sometimes subdivided into 
separate compartments by the unequal advance of the larger 
fans. The occasional occurrence of recent fault scarps which 
traverse the fans near their apex, parallel to the mountain base, 
thus indicating renewed movement on the fault by which the 
mountain block was uplifted. The shore lines of different types 
traced at various levels along the mountain slopes. The moder- 
ate size of the deltas at the highest shore-line level, because the 
streams of that stage were devoted to filling the long bays formed 
by drowning the valleys in the mountains ; the much larger 
size of the deltas of lower levels, because much of the uncon- 
solidated filling of the drowned valleys was then rapidly washed 
out into the main body of the lake. The occurrence of Bonne- 
ville shore hues on the slopes of previously formed fans of large 
size, thus indicating that a long period of arid cKmate had pre- 
ceded a relatively short-lived period of humid chmate. The 
vastly greater mass of the mountains than that of the fans at 
the ravine mouths, thus indicating that the period occupied 
in building the fans was a very small fraction of an entire cycle 
of mountain erosion ; hence the vanishingly short duration of 
the humid cKmate of Lake Bonneville, in comparison either 
with the cycle of mountain erosion that preceded, or with the 
cycle that is now following the block faulting of the region. 
The redemption of all the irrigable parts of the desert by the 
settlement of the Mormons, begun seventy years ago. The 
recent shrinking of Great Salt lake, as if on account of the with- 



112 DAILY ITINERARY OF THE EXCURSION 

drawal of its few inflowing streams for irrigation. The great 
density of the lake waters, as indicated by the ease of floating 
in them ; and their extreme salinity, as indicated by the pain- 
ful smarting caused if the water enters one's eyes or ears — an 
experiment that is not worth trying. 

It was at Ogden that the two sections of the first Pacific railroad 
— the Union Pacific from the east and the Central Pacific from 
the west — were united in 1866. The line of the Union Pacific 
comes through the Wasatch range by the deep canyon of Weber 
river. We turn southward from Ogden to Salt Lake city, and 
on the way have a fine exhibition of the dissected fault scarp of 
the Wasatch front, with its faceted spur ends and high-level 
shore lines. Some of the alluvial fans near our route are crossed 
by recent low fault scarps. 

Thirty-fourth and fifth Days, Tuesday and Wednesday, September 

24 and 25 

EXCURSIONS NEAR SALT LAKE CITY AND PROVO, UTAH 

Details of these excursions not being completed at the time of 
printing this Guide, they will be announced later, during the 
journey. They will probably include a visit to the dissected 
fault scarp of the Wasatch range, possibly at a point w^here 
glacial moraines advance upon the piedmont plain and suft'er 
recent faulting along the mountain base line ; a visit to some 
mines in the Oquirrh range, a good example of one of the Basin 
ranges, with prevailingly subdued forms and waste-covered 
slopes, and with a fine series of Bonneville shore lines around its 
northern end ; and a visit to the recent fault scarps at the base 
of the Wasatch range east of Provo, on the afternoon of our de- 
parture for Colorado. Later in that afternoon, we follow up 
the valley of Spanish fork, where it flows westward through the 



GRAND JUNCTION TO GLENWOOD SPRINGS, COLO. 113 

Wasatch range south of Provo, and thus enter the northern part 
of the Plateau province, in which we continue all night. 



Thirty-sixth Day, Thursday, September 26 
GRAND JUNCTION TO GLENWOOD SPRINGS, COLO. 

In the early morning before daybreak, we cross Green river, 
a short distance south of its canyon through a high plateau, of 
which the elaborately dissected south-facing escarpment is 
known as the Book cliffs, one of the strongest examples of its 
kind in the region. To the southwest is the greatly denuded 
region of the San Rafael swell, in which a dayhght trip barely 
shows the summits of the laccolithic Henry mountains, made 
famous by Gilbert's early studies. As we progress eastward, 
a gradual transition is made to more disturbed structures ; and 
thus we leave the Plateau province and enter the Rocky moun- 
tain system. Here we reach the valley of Grand river, which 
unites with the Green to form the Colorado. At the junction 
of Gunnison river, which comes from the southeast, with the 
upper Grand, which comes from the northeast, lies Grand 
Junction with its extensive irrigated orchards ; here we spend 
the morning. 

In the afternoon we follow up the valley of Grand river, which 
is alternately narrow in the resistant rocks, especially in the 
fundamental crystallines and the basal sandstones of their cov- 
ering strata, or maturely opened in younger structures of less 
resistance. After reaching Glenwood Springs, we continue 
up the canyon of the Grand river, there eroded through the 
covering sandstones into the underlying granites ; here we pass 
the works of the Central Colorado Power Company, first seeing 
the power house, to which the water is led through pressure 
pipes from a tunnel in the canyon wall, and then, two and a half 



114 



DAILY ITINERARY OF THE EXCURSION 



miles farther up the canyon, the dam where water is diverted 
from the river to the tunnel. The transmission hues of this 
company, constructed at great expense, extend to Denver, 153 
miles distant ; we shall see them crossing certain mountain 
passes at altitudes of 10,000 and 11,000 feet. 

On approaching the town of Gypsum, the resistant rocks are 
left behind and the valley opens to mature form ; here a curious 
feature is seen in an isolated lava flow of recent date far in the 
continental interior. Its vent is on the northern valley side ; 
the flow spreads across the valley floor and pushes the river 
against the southern side. This lava flow is one of the not fre- 
quent examples of a first eruption in a non-volcanic district; 
it thus stands in strong contrast with the recent flows of central 
France, which are the closing episodes in a volcanic period of 
long duration. We return to Glenwood Springs, where we pass 
the evening. Towards midnight our train takes us up the valley 
of Eagle river toward the continental divide in the Sawatch 
range. 

Thirty-seventh Day, Friday, September 27 

EAGER MAN PASS TO DENVER, COLO. 

The morning opens on the northern side of the valley, or 
glacial trough, of Fryingpan river, a branch of Eagle river, which 
here drains the western spurs of the Sawatch range, a part of 
the continental divide. Fine bank moraines are seen near the 
track. A hanging side valley joins the main vaUey from the 
south, and a delicate terminal moraine is seen crossing the 
glaciated ledges just beneath the hanging valley mouth. We 
turn northeast up another hanging side valley of pronouncedly 
trough-like form, and follow it past the head of its deepened 
trough, where the huge rock cliffs have gained the name of Hell- 
gate. The top of a fine mountain dome, of typically subdued 



HAGERMAN PASS TO DENVER, COLO. 115 

form although about 13,000 feet in height, is seen ahead; it 
forms part of the continental divide. We continue eastward up 
the shallower trough floor to the western entrance of a tunnel 
under Hagerman pass in the crest of the Sawatch range. Here 
we walk over the crest, leaving the waters of the Colorado sys- 
tem behind us, as we ascend the graded and grassy western 
slope to the pass, and then turning for a short ascent to the 
summit of a half-dome, surmounted by a group of ungraded 
granite crags, whence we look down on the headwaters of the 
Arkansas-Mississippi system. 

The most striking feature of the view results from the unsym- 
metrical distribution of glacial erosion. Owing to the west 
winds, the present action of which is seen in the forms assumed 
by stunted trees near the pass, the glaciers formed on the western 
slope were small ; those in the eastern valleys were much larger, 
and there the valley heads were enlarged into cirques. Some- 
times a cirque has consumed only a small part of a subdued 
domelike mountain top ; other cirques have consumed more than 
half of a dome, and as a result the mountain crest has a very 
unsymmetrical cross profile. 

We descend into the rugged eastern cirques by an easy path, 
take the train at the east end of the tunnel, and then follow the 
south side of a well-developed trough system to the terminal 
moraine, which, with several others of similar origin, advances 
into the open intermont basin of the upper Arkansas river. 
The famous silver-mining town of Leadville lies on the slope to 
the east. As we turn southward along the flat basin floor, fine 
views are gained of the huge undissected body of Mt. Massive 
on the west. Large moraines stretch eastward into the basin 
from a valley trough on the south side of Mt. Elbert ; the Twin 
lakes lie in the morainic basin, not seen from the train ; the level 
of the lakes has been raised to increase their storage capacity; 



ii6 DAILY ITINERARY OF THE EXCURSION 

the water is drawn off to the river, to be diverted in irrigating 
canals many miles downstream, east of the mountains; but the 
farmers who have earlier rights to the natural flow of the Arkan- 
sas insist that the later comers small not draw off as much water 
to their canals as they turn into the river from the Twin lakes 
reservoir, for part of that supply is Tost by evaporation on the way. 

Still larger moraines south of those of Twin lakes advance so far 
that they push the Arkansas close against the eastern side of its 
basin, where it undercuts the rocky slopes in a narrow gorge ; 
at the upper end of the gorge lies the village of Granite. After 
passing this gorge, the basin opens again, and we begin the oblique 
ascent of the eastern slope, among abundant granite bowlders 
of local weathering. We here enjoy a fine view of the southern 
half of the Arkansas basin ; the aggraded floor slopes eastward 
from the higher mountains of the Sawatch range on the west ; the 
town of Buena Vista lies in the middle of the basin ; the river, 
heavily freighted with coarse bowlders, is pushed close along the 
base of the eastern slope. Three summits in the Sawatch range are 
known as the College peaks ; to the northwest is Mt. Harvard, 
to the west, Mt. Yale, both over 14,000 feet : these two peaks were 
first ascended and measured in 1869 by a party led by J. D. Whit- 
ney, a graduate of Yale and then professor at Harvard ; the 
director of the present Excursion was a member of the party, 
and was the first to reach these two summits. Mt. Princeton, 
next to the south, was named a few years later by Hayden's 
survey party, among whom was Henry Gannett, also a member 
of Whitney's party of 1869. Moraines extend out upon the 
basin floor from the valleys between the peaks. 

We turn eastward into a side valley, and soon cross over an 
open pass by which we enter South park, one of the highest of 
those broad, intermont plains which characterize this part of the 
Rocky mountains^ It affords excellent pasture in summer, but 



HAGERMAN PASS TO DENVER, COLO. 117 

is too cold for cattle in winter. Pikes peak rises to the east, a 
great monadnock standing about 4000 feet above the Rocky 
mountain highland in this district. Cripple creek, a famous 
gold-mining camp, now past its prime, lies on the highland to 
the south of Pikes peak. We cross the park and leave its east- 
ern side by a canyon which the South Platte river has cut in the 
granitic highland ; but we soon turn out of the canyon to cross 
a gravel -covered district at an altitude of about 10,000 feet, 
northwest of Pikes peak ; and then descend rapidly to the Great 
plains at the base of the mountains. 

At the point where we descend, the usual nearly rectilinear, 
north-south trend of the mountain front is interrupted by a west- 
ward embayment, at the apex of which Hes the town of Manitou. 
The greater part of the embayment is occupied by inclined sand- 
stones which dip southeastward from the mountains ; they fre- 
Cjuently form monoclinal ridges, of which the most striking mem- 
bers are included in the " Garden of the Gods," a few miles to 
the north. The southwestern side of the embayment is a fine 
example of a fault-line escarpment ; here the monoclinal strata 
are cut off, one after the other, along an oblique hne. Many 
springs rise along the fault line. The mountain front is hmited 
by the same fault line instead of by a monoclinal flexure for 
several miles to the southeast ; and the mountain front in 
that district is therefore a dissected fault-line scarp, instead of 
a stripped surface of ancient erosion. 

We run out of the embayment to Colorado Springs, noted as 
a residential city on the border of the plains ; a low mound on 
the plains a little farther east is known as Mt. Washington, be- 
cause its altitude is the same as that of the dominating summit 
of the White mountains in New England. We turn north and 
approach the mountain front where it advances at the northern 
border of the Manitou embayment, and continue ascending the 



II 



DAILY ITINERARY OF THE EXCURSION 



apparently subsequent valley of Fountain creek, a tributary 
of the Arkansas, inclosed on the east by a retreating cuesta- 
like escarpment of plains strata. The valley narrows to its 
head, where the railroad, running close to the mountain base, 
passes over to a similar valley of northward discharge, which 
leads to the vallev of the South Platte, in which lies the citv of 




iiL.. J4. Fiood in Cherry Creek. Denver, Colorado. 

Denver, the largest city of the plains ; we arrive there late in the 
evening. The streams of this district are subject to sudden 
floods, and the detention of trains bv " washouts " is not un- 



common. 



Thirty- eighth Day, Saturday, September 29 



FROM DENVER TO THE CONTINENTAL DIVIDE AND RETURN 

A local train carries us northward from Denver ; we soon cross 
the valley of Clear creek, broadly excavated below the general 
level of the plains, to which ascent is then gradually made north- 
westward. As we rise it may be perceived that the present 



FROM DENVER TO THE CONTINENTAL DIVIDE 119 

valley floor of Clear creek, which flows eastward from the moun- 
tains, is bordered below the plains level by the remnants of an 
earlier valley floor, which now form lateral terraces, more or 
less dissected by side streams. Irrigating canals or " ditches," 
running along the valley sides, mark the boundary between the 
abundant vegetation of cultivated field and orchards and the 
scanty herbage of the treeless plains. 

The simple margin of the Front range, with its highlands and 
its monadnocks, is now well seen to the west. Two lava-capped 
table mountains stand north and south of Clear creek near its 
exit from its gorge in the highland. To the south. Green 
mountain is an unconsumed remnant of the plains strata, not 
wholly removed in the general peneplanation of these weaker 
rocks. On approaching the mountains, the plains strata, 
exhibited in the cuts of the winding railroad as it ascends to 
the full height of the plains, are seen to be steeply inclined for 
a mile or more from the mountain base ; the inclined strata are 
evenly truncated and covered with " wash " from the moun- 
tains. This makes it clear that the broad surface of the plains 
between the shallow valleys is not a surface of original deposi- 
tion, but a surface of penultimate planation. It may be noted 
that the erosion of the existing valleys below the plains does 
not require the uplift of the region : in view of the great dis- 
tance from the sea it suffices to assume a slight change in the 
relation of stream activity to the load of waste which the streams 
have to carry, to cause them either to degrade or to aggrade their 
previously graded courses ; and this change can be brought about 
by variation of climate as well as by a regional upHft or depression. 

Some of the more resistant plains strata near the base of the 
series form monoclinal ridges or foothills, frequently notched 
by consequent stream channels, and separated from the mountain 
base by a longitudinal depression, consisting of many confluent 



120 DAILY ITINERARY OF THE EXCURSION 

subsequent valleys. The simple mountain front is a geographi- 
cal fossil ; it is part of the ancient erosion surface on which 
the plains strata were deposited ; the ancient surface was long 
preserved by burial ; the compound mass was then flexed, 
peneplained, uplifted, and eroded; thus the covering strata are 
now worn off from their foundation ; the ancient surface is thus 
revealed in the simple spurless mountain front of to-day ; it is 
somewhat overlapped by unremoved strata near the base, some- 
what the worse for wear near the top, and repeatedly cut down 
by the valleys of outflowing streams. Occasionally some of 
the most resistant basal red sandstones chng to the sloping 
mountain front and rise to the top; we see good examples of 
these as we reach the mountain base ; they become stronger a 
little farther north, and rise in peaks even above the level of the 
crystalline highland; these are known, when seen from the 
plains, as the " Flatirons," from their triangular form and smooth 
exterior slope. As we skirt the mountain border, a fine prospect 
is afforded over the treeless plains, which extend eastward more 
than 500 miles. 

We turn from the mountain front into the submature gorge 
of South Boulder creek, deep cut in the granite rocks of the 
Front range highland, and follow the southern wall at mid- 
height, cutting through many spurs in short tunnels. The 
village of Eldorado Springs is seen below us as we enter the 
gorge ; the contact of the resistant basal members of the plains 
strata and their crystalline foundation surface, both steeply 
inclined, is well shown on the northern side of the gorge. The 
fall of the creek being more rapid than the grade of the railroad, 
the depth of creek below the track decreases, and after a few 
miles we find ourselves running close to the bottom of the gorge. 
We then rather abruptly enter the broad basin of Boulder park, 
a glaciated trough, with truncated spurs and hanging lateral 



FROM DENVER TO THE CONTINENTAL DIVIDE 121 

valleys. The small volume of morainal material at the lower 
end of the trough, where we enter it, is interesting in view of the 
great amount of glacial erosion indicated by the breadth and 
depth of the trough. 

After following the trough floor for several miles, past the small 
summer resort of Tolland, we turn back by a semicircular curve 
and ascend the northern trough side by a double loop; then 
pass northward out of this trough into a smaller one, which we 
follow up to a group cf well-defined cirques, excavated in the 
eastern slope of some low monadnock domes which here surmount 
the highland and determine the range crest. We loop around 
the head walls of the cirques, and then again pags northward to 
the southern wall of the great glacial trough of Middle Boulder 
creek, which Hke South Boulder creek is a tributary of the Platte- 
Missouri-Mississippi system. This trough heads in a strong 
rock step, above which is a fine group of cirques. We pass around 
the mountain crest to the southwest, and there find that we have 
crossed the continental divide, as the slope now descends west- 
ward to Middle park, a large intermont depression, the waters 
of which flow by Grand river to the Colorado and then to the 
Pacific ocean. Here lies the switching station of Corona in 
a long snowshed, where we leave the train for an ascent by an 
easy stroll up the western slope, to the monadnock domes which 
form the crest of the range. 

Glacial action is not apparent here ; but on reaching the crest 
we find that the convex domes are more than half destroyed by 
the excavation of strongly concave cirques on the eastern slope. 
The view here deserves careful study ; it is by no means Alpine, 
but it is thoroughly characteristic of the Rocky mountains. 
To the east the gently sloping highlands of the Front range are 
surmounted by occasional monadnocks and dissected by glacial 
troughs and normal stream valleys; far in the distance stretch 



122 DAILY ITINERARY OF THE EXCURSION 

the Great plains, with their oceanlike horizon. To the south 
rises James peak, singular in preserving a small part of its pre- 
glacial dome summit between great cirques that encroach on all 
sides. To the north rise the Arapahoe peaks, sharpened by 
a more pronounced enlargement of several cirques; in one of 
them lies a small glacier. Next to the east is Bald mountain, 
of less height and well-rounded form, apparently unaffected by 
glacial action ; it is a good example of Mittelgehirgsjorm at the 
height of Hochgehirge. To the west, the descent is rapid to the 
broad, high-level basin of Middle park. 

The mature glacial troughs and normal valleys of the Boulder 
creeks are evidently of later origin than the gently undulating 
highland in which they are incised. The highland surface 
shows the features of old age. It must have had less altitude 
and less eastward inclination from the range crest to the range 
front, while it was worn down to its gently undulating relief, 
which here and there deserved to be called a peneplain ; but it 
could not have been a lowland near sea level, because its rivers 
even in their old age must have had some slope to the sea, and in 
view of their great length of nearly 1500 miles, their headwaters 
may well have had an altitude of 5000 or 6000 feet. The pene- 
plain now stands at altitudes of from 9000 to 11,000 feet; hence 
it must have suffered strong regional uplift, or up-arching, since 
peneplanation. Before this regional uplift, the surface of the 
peneplain on the crystalline rocks of the mountains area must 
have been continued by a smoother peneplain on the weak rocks 
of the plains area; it is only since the uplift of mountains and 
plains together that the plains have been worn down lower than 
the mountainous highland. The height of the mountains over 
the plains is therefore not so much the result of the local uplift 
of the mountains, as of the widespread erosion of the plains 
after a broad uplift of the whole region. 



PUEBLO TO RATON, COLO. 



123 



The peneplanation of the region must have occurred after the 
formation of the flexure by which the mountain border is de- 
termined, for the even surface of the highlands makes a well- 
defined angle of 30° or 40° with the dip of the inclined basal 
members of the plains strata. Hence the surface of the high- 
lands is of much later date than the inclined ancient planation 
surface — the geographical fossil — revealed by stripping the 
plains strata from the mountain front; a long period of deposi- 
tion followed by a strong monoclinal bending must have elapsed 
between the two great periods of erosion in which the resistant 
crystalline rocks of the mountain mass were worn down to low 
relief. The Front range is therefore a morvan ; its earlier pene- 
plain was remarkably smooth ; the covering strata measured 
thousands of feet in thickness ; the tilting of the compound mass 
was accomplished by a strong monoclinal flexure sometimes 
broken by faulting ; the later peneplain retained numerous monad- 
nocks in the area of crystalline rocks ; the regional elevation was 
accompanied by arching, which defined the crest of the range and 
gave the eastern part of the highland its manifest eastward in- 
clination ; and the cycle of erosion thus introduced has already 
attained an old stage on the weak strata of the plains and early 
maturity in the hard rocks of the mountains, with recent episodes 
of glaciation in the higher valleys and of renewed valley erosion 
in the plains. 

The afternoon return to Denver reverses the line of the morn- 
ing ascent. 

Thirty-ninth Day, Sunday, September 29 

PUEBLO, COLO., TO RATON, N.M.i 

The night run southward from Denver has brought us past 
Colorado Springs to Pueblo on the Arkansas river, some 20 

1 Based from thirty- ninth to forty-fifth days in part on notes by W. T. Lee, 
U. S. Geological Survey. 



124 DAILY ITINERARY OF THE EXCURSION 

miles east of the mountains. There we turn west up the river, 
and pass into its canyon in the Front range, where we find our- 
selves at daybreak. It is here that the Arkansas escapes from 
the southern end of the intermont basin, which we saw on our 
thirty-seventh day. We return through the deepest and narrow- 
est part of the canyon, known as the Royal gorge, cut in crystal- 
line rocks, with unusually steep walls. 

Below the gorge, we pass Canyon city and Florence, which 
with their irrigated fields lie near the mountain base in a denuded 
embayment similar to the one we saw farther north at Manitou; 
monoclinal foot-hill ridges may be seen following the border of 
the embayment to the north. We return to Pueblo and then 
run about 80 miles farther down the irrigated Arkansas valley, 
on the way passing Rockyford, famous for its melons. At 
La Junta we turn southwestward and travel across the pene- 
plain of the Great plains, with unconsumed mesas on either side, 
to the valley of the Purgatoire river, — '' Picketwire " in cowboy 
English, — a branch of the Arkansas, in the foothills of the 
mountains at Trinidad. There the most striking object is Raton 
mesa, a lava-capped mass, culminating in Fishers peak, the alti- 
tude of which testifies to the depth of erosion — more than 
3000 feet — by which the surrounding peneplain was produced. 
To the west rise the Spanish peaks (not to be confused with a 
similarly named section of the Wasatch range in Utah), a deeply 
dissected volcanic mass, around the base of which many dikes 
take the form of natural walls. Coal is mined in the dissected 
plateau northwest of Trinidad ; the coal beds occur at horizons 
above a conspicuous gray cliff. 

We ascend toward the south and tunnel through Raton pass, 
west of the mesa of the same name ; here we cross the Colorado- 
New Mexico boundary; descent is then made to Raton, where 
our train turns eastward on another line to see something more 



PECOS RIVER TO ALBUQUERQUE AND BEYOND 125 

of the volcanic district, which extends nearly 100 miles from 
Raton mesa to the IMesa de Maya. The lava sheets are of 
various ages ; the oldest cover the highest mesas to the north, 
and rest upon a high-level peneplain formed on the plains strata ; 
flows of much younger date are crossed by our road or cap low 
mesas to the south. A very recent and well-formed volcanic 
cone, Mt. Capuhn, rises not far from the track. We return to 
Raton in the evening, and continue our journey southward 
through the night. 

Fortieth Day, Monday, September 30 
PECOS RIVER TO ALBUQUERQUE AND BEYOND 

Our itinerary here is not definitely settled at the time of 
preparing this Guide ; hence details must be left for the daily 
bulletins issued on the train. During the night we have followed 
near the eastern base of the Rocky mountains, and in the early 
morning turn westward around their southern end. Here the 
Pecos river, a tributary of the Rio Grande, flows south of 
our crossing as a consequent stream through the subsequent 
monoclinal sandstone ridges that encircle the end of the range; 
but upstream from our crossing the river follows a subsequent 
valley between the mountain slope and the escarpment of 
Glorieta mesa, really a cuesta, on the southwest ; and the rail- 
road runs between the two. The mountains in the north have 
subdued forms. Santa Fe, the site of an ancient Indian town, 
occupied by the Spaniards three centuries ago, lies in the western 
foothills of the mountains, a Kttle north of our route. Spanish 
names abound in all this region. We round the northernmost 
point of the mesa, and cross a divide to a tributary of the Rio 
Grande, which we follow southwest to the main river. Near 
Cerrillos station, we pass between two laccolithic mountains, 



126 DAILY ITINERARY OF THE EXCURSION 

Los Cerrillos on the north, noted for their turquoise, and the 
Ortiz mountains on the south. A few miles beyond we enter the 
valley of the Rio Grande, which has come through a canyon 
in its escape from the great intermont basin of San Luis valley, 
the southernmost example of its kind in the Rocky mountains 
system. The valley which we now follow to the south is an 
aggraded depression formed by the eastward tilting of two fault 
blocks, of which the eastern one, Sandia mountain, with its 
dissected fault scarp facing us, rises nearly to 12,000 feet altitude, 
or 7000 feet above the valley. This district is therefore a part 
of the Basin range province, which here advances far eastward 
to meet the Great plains in eastern New Mexico, and cuts off 
the Rocky mountain system from the southern extension 
formerly attributed to it. To the west, across the river, the 
Albuquerque volcanoes surmount an upland of sand and gravel. 
The Indian pueblo of Santo Domingo is near the railroad on the 
west. 

We continue southward along the Rio Grande past Albu- 
querque and the Indian pueblo of Isleta, and then turn westward ; 
beyond Rio Puerco and up its northwest branch, Rio San Jose, 
we come to the same series of strata that is exposed east of Rio 
Grande, the members first seen here, dipping northeast, corre- 
sponding to those forming the back (eastern) slope of Sandia 
mountain. Some recent lava flows are passed ; the Indian 
pueblo of Laguna hes near the railroad ; the more famous 
ancient pueblo of Acoma hes about 15 miles to the southwest 
of our route. To the northwest Mt. Taylor, a dissected volcano, 
rises over a lava-capped plateau, but the views of it from the 
railway are inadequate and fail to give a proper conception of 
its great size. During the night of our westward journey, but 
probably by daylight on our return (forty-sixth day), we pass 
north of the denuded and subdued mass of the Zuni mountains, 



PECOS RIVER TO ALBUQUERQUE AND BEYOND 127 

the crystalline rocks of which belong to the foundation of the 
heavy series of strata which we have seen dipping north and 
northeast after crossing the Rio Grande ; it is this series of 
strata that is upHfted in Sandia mountain, east of the Rio Grande, 
but the uplift there was not great enough to expose the funda- 
mental rocks. We follow a broad subsequent valley excavated 
along a belt of weak strata which dip gently from the crystalline 
rocks northward beneath a heavy series of red sandstones ; 
these rise in a strong escarpment, peculiar in having very little 
talus because the sandstone crumbles to sand instead of faUing 
in large blocks. The north south continental divide crosses this 
east-west subsequent valley; the eastern drainage runs to the 
Rio Grande and the Gulf of Mexico ; the western drainage to a 
second Rio Puerco, and then by the Little Colorado to the 
Colorado river of the West and the Pacific. Beyond the divide, 
the subsequent valley and the inclosing ridge with its red sand- 
stone escarpment turn southward around the western side of the 
Zuni mountain uphf t ; we continue westward through an open 
consequent breach in the ridge, in which the dip of the sand- 
stones rapidly increases ; we then cross another north-south 
subsequent valley, and pass through a breach in a ridge of 
vertical gray sandstones ; and after crossing still another subse- 
quent valley, come to an upland of horizontal strata, in which 
coal is mined ; here is the town of Gallup. We have thus crossed 
the great Nutria monocline, one of the grandest structures of 
its kind in the West ; Button has described it admirably, and has 
emphasized the enormous erosion that the eastern uplifted area 
has suffered. The line of the monocHne is marked by the ridge 
of vertical sandstones, with older strata on the east and younger 
strata on the west, all now reduced to about the same relief. 
The vast amount of denudation thus indicated may be referred 
to the earlier cycle of erosion of the Plateau province ; in this 



128 DAILY ITINERARY OF THE EXCURSION 

district the later cycle, now current, has not yet succeeded 

in producing deep dissection. The strong relief possessed by 

Sandia mountain suggests that its uphft is of much later date 
than that of the Nutria monocline. 

Forty-first Day, Tuesday, October i 
WINSLOW, ARIZ., TO THE GRAND CANYON OF THE COLORADO 

The morning finds us on the undissected plateau country drained 
northwestward by the Little Colorado. A low escarpment 
to the north is pecuHar in possessing an extremely coarse talus 
of huge blocks, which are broken from the capping sandstone by 
the sapping of the underlying clays, thus contrasting strongly 
with the much higher red sandstone escarpment seen north of 
the Zuni mountains, where the talus was scanty. The sandstone 
escarpment here seen contains many fragments of silicified 
wood, and at an outlier south of the railroad, reached from 
Adamana station, abundant tree trunks have given the locaHty 
the name of the Petrified Forest ; we may be able to visit it, 
either going or coming. The widespread removal of the sand- 
stones and clays of this escarpment, and of many other over; 
lying formations which have now retreated far to the north, indi- 
cates that the area of resistant limestones to the south of us is 
a stripped plateau, and that the broad valley of the Little 
Colorado which we are following is a subsequent valley still 
exhibiting the features of the old stage of the earher cycle, al- 
though broad uplift has introduced it into the new cycle, now 
current. Farther downstream, to the northwest, the Little 
Colorado has followed the example of the main Colorado in tak- 
ing advantage of the new uplift to intrench itself in a canyon, 
deep below the denuded surface of the earlier cycle ; but here that 
work is still potential, not yet actual. 



AT THE GRAND CANYON OF THE COLORADO 129 

We cross the Little Colorado at Winslow ; it follows the old 
subsequent valley lowland to the northwest; we obliquely 
ascend the long slope of the stripped limestone plateau to the 
west. Occasional remnants of overlying sandstones appear in 
curiously isolated forms ; a small consequent stream has cut a 
narrow trench in the limestones, known as Canyon Diablo. 
The dissected volcano, Mt. San Francisco, rises ahead of us, 
v/ith pine forests on its flanks and snow patches on its summit ; 
we pass it and its dependent volcanic forms on the south ; at 
Flagstaff the old stage road ran north to the Colorado can- 
yon. Forested volcanic mountains in advanced, subdued stages 
of dissection continue to diversify the barren plateau. At 
Williams, we turn north by a branch line ; the volcanic moun- 
tains are soon left behind ; with the gradual ascent of the sur- 
face, tree growth sets in and we enter the Coconino forest. Red 
butte, a lava-capped outlier of higher strata, elsewhere stripped 
away for scores of miles, rises over the forest to the east. We 
gain a brief ghmpse of the Grand canyon ; its farther wall and 
the even sky Hne of the Kaibab plateau are seen miles away to 
the north across a void space, but the bottom of the canyon is 
far below our high line of sight. A shght rise of the ground closes 
the view ; we reach the end of the line and walk up the httle 
slope to the canyon rim. 

The end of the afternoon is free for short walks east or west 
to the promontories of the plateau. We spend this and the 
following night at El Tovar hotel. 

Forty-second and third Days, Wednesday and Thursday, October 2 and 3 
AT THE GRAND CANYON OF THE COLOR.ADO 

The descent into the canyon is planned for October 2 ; for the 
next day there is no special plan till the early evening, when we 
take train for Phoenix. 



I30 



DAILY ITINERARY OF THE EXCURSION 



The features of special interest to be noted during our stay at 
the canyon are as follows : The compound structure of the 
plateau mass as revealed in the canyon walls ; namely, a founda- 
tion of deformed and resistant crystalHne sheets, commonly 
spoken of as the '' granite " ; a heavy series of strata, resting 
unconformably on a remarkably smooth floor or planation 
surface of the crystaUine rocks, incHned to the southeast, and 
truncated in wedgehke form by a second planation surface 
which transects the crystaUine rocks as well ; a heavy horizontal 
series which covers both the older rock series unconformably and 
builds up the even surface of the plateaus. The three members of 
the tripartite mass may be conveniently spoken of as the founda- 
tion, the wedge series, and the plateau series. The wedge 
series is here cut off by a fault, which uplifts the , foundation 
crystallines on the east ; the fault was evidently of earHer date 
than the second planation, as it is evenly crossed by the plateau 
series, for which the second planation prepared the floor. Some 
twenty miles to the east, the wedge series is seen again and in 
much greater volume ; its inclined strata, mostly sandstones 
and slates, often of bright red color, there measure about ii,ooo 
feet in thickness ; their uppermost members are not seen because 
the monoclinal flexure, which limits tlie Kaibab plateau on the 
east, carries all these older structures below the river level in the 
Marble platform block. 

The plateau series includes a resistant sandstone at the base, 
a heavy and resistant limestone near the middle, and several 
resistant sandstones and limestones near the top, all these being 
separated by weaker strata ; thus the series may be spoken of 
as including several cliff makers and alternate slope makers. 
The topmost member of the series here visible is by no means 
the top of the entire stratified series in the Plateau province ; 
the uppermost members rise, from 70 to 100 miles north of the 



AT THE GRAND CANYON OF THE COLORADO 131 

canyon, in a series of great escarpments to the High plateaus of 
southern Utah ; hence they may be called the high-plateau series. 
They have been stripped from a vast area of country, and only 
occasional outliers of their lowest members, as seen in Red butte 
south of the canyon, now remain as witnesses of their original 
extension. It is of geological interest to note that the middle 
and capping members of the plateau series are of Carboniferous 
date, and that the basal members are of Cambrian date ; all 
the formations, from the Cambrian sandstones at the base of 
the plateau series, to the Eocene strata at the top of the high- 
plateau series, follow in conformable sequence, except for a 
slight unconformity by erosion without deformation in the 
Permian ; the wedge series is pre-Cambrian, being separated 
from the Cambrian by a completed C3^cle of ancient erosion ; 
the foundation rocks are of complicated history, but are older 
than the wedge series by another completed cycle of erosion ; 
thus the perspective of the past opens to us, through the illim- 
itable " corridors of time." 

None of the larger faults and flexures of the Plateau province 
are visible from our point of view at the canyon, though glimpses 
of the flexure at the eastern side of the Kaibab may perhaps be 
gained from some of the promontories. A small fault traverses 
the plateau a short distance west of El Tovar ; it is presumably 
of the same date as the greater ones; it is now significant only in 
producing a dull and low fault-hne scarp, along the base of which 
a fault-line valley on the plateau surface leads to the head of a 
side canyon. 

The evidence in favor of an earlier cycle of erosion, in which 
the Plateau province was broadly denuded before being broadly 
uplifted to its present altitude, is not clearly seen near the canyon, 
but it has been well substantiated by several observers elsewhere. 
We can here see its perfect accomplishment in the even sky line 



132 DAILY ITINERARY OF THE EXCURSION 

of the Kaibab plateau to the north ; but that plateau, when 
visited, is found to be maturely dissected by shallow ramifying 
valleys, while the lower Marble platform on the east and the 
lower Kanab plateau on the west, capped by the same limestones 
as the Kaibab, are much less dissected ; hence it is supposed that 
the present surface of the Kaibab block rose looo feet or so above 
the lowland surfaces of the adjacent blocks at the close of the 
first cycle of plateau development. 

The canyon is of unsymmetrical cross section ; the river is 
much nearer to the Coconino plateau on the south than to the 
Kaibab plateau on the north, because of a gentle southward dip 
of the strata. The form of the canyon walls responds so closely 
to the structures of the plateau mass that these structures, 
however long they have been monopolized by geology, must 
inevitably be mentioned in any detailed geographical account 
of the canyon ; and all the more because of their manifest expo- 
sures in the absence of abundant vegetation. The hard crys- 
talline rocks of the foundation hold the bottom of the canyon 
narrow ; hence that part is often called the " inner gorge." The 
cliffs and slopes of the higher walls follow their controlling 
structures with accuracy. The cliff face of the heavy middle 
limestones, themselves of the usual bluish color of such rocks, 
is stained by the wash from the overlying red shale, and hence 
the Kmestone cUffs are called the " red wall." A platform 
is stripped on the red-wall cKffs as well as on the basal sandstones ; 
but while the sandstone platform at the lower level, underlaid 
by the resistant foundation, is little dissected, the Hmestone plat- 
form, at the higher level and underlaid by weak shales, is much 
more dissected ; the sandstone platform is cut back by each 
wet-weather side stream in a narrow and sharp-headed ravine, 
while between the ravines it advances in broadly rounded promon- 
tories ; the red-wall chffs under the Hmestone platform retreat 



AT THE GR.\ND CANYON OF THE COLOR.\DO 



^33 



in great rounded amphitheaters and advance in sharp cusps. 
The high-level chffs of the plateau rim recede in open embayments 
between blunt promontories. All these forms are the necessary 
and systematic result of normal erosion on a heavy mass of 
horizontal strata of varying resistance. Wind erosion is un- 
doubtedly of importance in the canyon, and some observers have 
attributed the great amphitheaters of the red-wall cliffs to its 
action ; but as a form-producing agency it is subordinate to the 
action of wash and creep under the persistent down-slope im- 
pulse of gravity. 

The main canyon is so young that its rapid river has hardly 
begun the widening of the canyon bottom ; indeed, in the hard 
rocks of the inner gorge, the river occupies the entire breadth of 
the cut, from wall to wall ; yet the canyon is ten or twelve 
miles wide at the plateau level. Hence, although the canyon is 
ordinarily spoken of as the work of river erosion, it must be 
tacitly understood that the larger part of the work has been 
done by the weathering and washing of the walls ; this river, 
like all rivers, has really carried away much more waste than it 
has cut. If the term '' erosion " is really Kmited to the destructive 
work of running streams, there are no such things as ''valleys of 
erosion," and still less " mountains of erosion "; but the common 
use of these phrases shows that the actual meaning of erosion, in 
practice, is much larger than its definition in textbooks. Water- 
falls on ungraded resistant strata are rare or unknown in the 
main river, but abundant in the wet-weather streams of the side 
canyons. All the side canyons, except the very smallest, are 
cut down to accordant junctions with the main river, even though 
they are only the work of intermittent streams. The largest 
one here seen is that of Bright Angel creek, which comes from a 
great embay ment in the Kaibab plateau. Great as is the work 
already accomplished in the excavation of the canyon, it is only 



134 



DAILY ITINERARY OF THE EXCURSION 



a small beginning of the task assigned to the river during the 
current cycle of erosion; the uncut plateaus to the north and 
south are very young. At the mouth of each side canyon, 
delta-like heaps of bowlders are swept out by occasional floods ; 
quiet pools occur above the bowlders, but where the river is 
constricted and steepened by the bowlder heaps, it rushes in 
violent rapids ; the rapids thus formed were the chief difhculty 
encountered by Powell in his exploration of the canyon by boats 
forty-live years ago. The heavy charge of silt borne by the 
rapid river scours and polishes the ledges and bowlders in its 
channel. 

Botanical geographers will find much to interest them in the 
flora of the canyon. A change of climate is indicated by a change 
of vegetation as one descends from the pine forest of the plateau 
to the bottom of the canyon, where the plants resemble those of 
northern Mexico. The prevaihng dryness of the air is indicated 
by the contrast between the warmth of sunshine and the coolness 
of shade, although this is less apparent in October than in July. 
The clearness of the air, taken with the magnitude of the canyon 
forms, makes it difficult to estimate distances. The strong, ruddy 
colors of the illuminated walls and the deep purple of the shadows 
cast by the promontories are striking features of the half hour 
before sunset ; the slow rise of the steel-blue shadow of the 
earth on the clear eastern sky, beneath the rosy twilight arch, is 
a characteristic feature of the following half hour. At night the 
visibility of stars close to the horizon tells us we are in an arid 
land. 

The improvement of our topographical maps is well illustrated 
by comparing the generalized contours on the smaller-scale 
sheets of earlier surveys of the plateau region with the accurate 
and expressive contours on the newer large-scale sheets of the 
can von. 



PHCENIX, ARIZ., TO THE ROOSEVELT DAM 135 

Forty-fourth and fifth Days, Friday and Saturday, October 4 and 5 
PHCENIX, ARIZ., TO THE ROOSEVELT DAM AND RETURN 

During the night we have gone a short distance west of Wil- 
liams on the main line of the Santa Fe railway to Ashfork, 
near the western margin of the Plateau province ; there we 
turned southward, descended the dissected escarpment in which 
the plateau country terminates, and entered the Basin range 
province. After running through various aggraded depressions 
in the complex of mountains, we pass between the Weaver 
mountains on the east and the Date-creek mountains on the 
west to a broad basin, in which we descend a long waste slope 
southward and thus reach the more open desert country of 
southwestern Arizona, in which the mountains are small and 
isolated, while the barren aggraded plains are of great extent. 
We turn eastward and during the early forenoon reach Phoenix 
in an irrigated district on Salt river, which comes from the moun- 
tains and the dissected scarp of the plateau country in the north- 
east, and joins the Gila a few miles west of Phoenix, on its way 
to the Colorado at Yuma, in the southwestern corner of Arizona. 

From Phoenix we make an excursion in automobiles about 
seventy miles eastward to the Roosevelt dam on Salt river, one 
of the greatest engineering works of the Reclamation service ; 
there we spend the night and return the next day. Our ride 
at first takes us through the irrigated gardens and fields near 
the city ; then out upon the desert. We soon pass between 
two isolated mountains, known as Tempe and Bell buttes, which 
appear to be the unconcealed summits of ranges, the lower 
slopes of which are buried in the heavy accumulation of detritus , 
a drill hole near Mesa went down 1305 feet, or 80 feet below 
sea level, without reaching bed rock. Groves of giant cactus 
are seen hereabouts. We go on about 25 miles, obhquely ascend- 



136 DAILY ITINERARY OF THE EXCURSION 

ing one of the long detrital slopes or " wash," so characteristic 
of piedmont desert topography; the detritus is coarse and its 
fall is about 100 feet to a mile near the mountain base ; the 
detritus is finer and the fall is reduced to 30 or 20 feet to a mile, 
ten or twelve miles from the mountains. 

The mountains are entered by an embayment in which stands 
the village of Goldfield ; Superstition range rises to the south, 
with strikingly irregular forms. The mountains, composed in 
part of great masses of lava, are crossed to the northeast 
by a well-made road, used in the construction of the Roosevelt 
dam ; its slanting location on a dissected fault scarp is a scenic 
feature of the trip. On approaching Roosevelt, we pass over the 
edge of a great fault block, consisting of granite overlaid by 
sedimentary strata ; the same rock series occurs in the rim of 
the Plateau prcTvince to the northeast. As seen from the lower 
ground, the dissected plateau rim is called the Mogollon range. 
The reservoir occupies the depression formed by the tilting of the 
fault block down from the plateau ; the dam is built across 
the gorge that has been eroded by Salt river through the upturned 
edge of the tilted block ; an excellent foundation was secured 
for the dam, as bed rock was discovered only a little below the 
low-water channel. 

After returning to Phoenix in the early afternoon of October 5 
take train northward, ascend to the plateau country in the night, 
and run eastward on our return journey. 

Forty-sixth and seventh Days, Sunday and Monday, October 6 and 7 
EASTWARD ACROSS THE PLATEAUS AND PLAINS 

The morning carries us up the broad valley of the Little 
Colorado, which we descended on October i ; in the afternoon 
we see part of the stretch which we passed in the night on our way 



EASTWARD ACROSS THE PLATEAUS AND PLAINS 137 

west ; a stop on the Nutria monocline will probably be made 
at this time. During the night we cross the Rio Grande, round 
the southern end of the Rocky mountains, follow their eastern 
base past Trinidad, and run out on the Great plains. The 
following day we run down the flood plain of the Arkansas valley 
below La Junta, through southeastern Colorado and south- 
western Kansas. Our view is rather narrowly limited by the 
bluffs of the valley side ; the aridity of the uplands leaves them 
almost uninhabited; irrigating canals are seen contouring the 
bluffs, but the small volume of the Arkansas, after nearly all 
of its water has been taken in the dry season for irrigation farther 
upstream, leaves parts of the valley floor hereabout uncultivated. 
At Las Animas, Purgatoire river enters from the dissected 
mesas in the southwest, some of them being part of the lava- 
covered district that is associated with the flows of Raton mesa. 
On nearing Hartland, Kansas, sand dunes become abundant 
on the plains south of the river, and so continue past Garden, 
while the bluffs of the upland margin approach the river on 
the north ; many undrained basins, holding wet-weather pools, 
occur among the dunes south of Cimarron ; near Dodge the 
dunes are less abundant. We turn across the low uplands to 
avoid a southward bend of the river, then cross it at Kinsley and 
traverse a broad plain to avoid the '' great bend " of the river 
to the north, crossing the river again at Hutchinson, and there 
turning from the Arkansas river eastward and northeastward 
across the broad interfiuve between this river and the Kansas, 
which is reached at Topeka. The interfiuve is faintly marked by 
low, gentle, ragged, east-facing escarpments, and abundantly 
dissected by shallow valleys, usually of insequent habit. From 
Topeka we run down the valley of Kansas river, its flood plain 
being inclosed by dissected bluffs on either side ; in the evening 
we reach Kansas city, at the confluence of the river of the same 



138 DAILY ITINERARY OF THE EXCURSION 

name with the Missouri ; the larger part of the city is in the 
state of Missouri, east of the confluence ; a smaller part is in 
the state of Kansas between the two rivers. 

Forty-eighth Day, Monday, October 8 
IN ST. LOUIS 

We have crossed during the night the maturely dissected 
uplands of Missouri, north of the Ozark plateau which occupies 
the southern part of the state ; the morning finds us approach- 
ing St. Louis, where we spend the day. Late in the evening, we 
take train for Memphis, Tenn. 

Forty-ninth Day, Wednesday, October 9 
FROM MEMPHIS, TENN., TO HELENA, ARK. 

The night journey from St. Louis has brought us over the 
northernmost part of the Mississippi embayment of the Gulf 
coastal plain, a maturely dissected district of moderate relief, 
and in the early forenoon we reach a point where the Mississippi 
for the last time in a long distance swings against the bluffs on 
the eastern side of its flood plain; there the city of Memphis 
occupies an advantageous position ; there the last one of many 
railroad bridges crosses the great river. The river then swings 
away from the eastern bluffs, and does not return to them for 
nearly 200 miles farther down its broad flood plain ; at that 
point the city of Vicksburg is located ; no large city is found 
on the east bank of the river between Memphis and Vicksburg. 
At about a quarter of the distance between these two cities the 
Mississippi makes its only swing against the bluffs on the western 
side of its flood plain, and there lies Helena, Arkansas, the only 
city of importance on the west bank of the river between St. Louis 
and the Gulf. 



FROM MEMPHIS, TENN., TO HELENA, ARK. 139 

. After a brief sight of Memphis, with special attention to the 
shipment of cotton on the levees, we board a steamboat for a 
seven-hour trip down the river to Helena. The chief features 
deserving attention are: Two old cut-off meanders, one 
known as Horn lake, about 12 miles below Memphis, the 
other as Beaverdam lake, about 15 miles above Helena, 
both on the east side of the river; the original connecting 
channels are now silted up, and the lakes are concealed by tree 
growth on the flood plains. A pronounced meander, known as 
Horseshoe bend, turns to the west, near the middle of our trip ; 
a recent cut-ofl at Council bend took place in 1874. The 
course of the river here is relatively simple, as contrasted with 
its well-developed meanders for a distance below Helena. The 
tendency of the meanders to enlarge their curves is shown by 
the erosion on the outer bank and deposition on the inner bank ; 
and their tendency to shift their position down valley is shown 
by the continuation of erosion and deposition beyond the end 
of the curves on which they began. The course of the deep- 
water channel always Kes near the outer side of the pronounced 
meanders; hence steamboats, in passing from one curve to 
the next, must " cross over " at the intermediate point or tan- 
gent of inflexion; it is chiefly at these ''crossings" that the 
navigation of the river is difflcult. The absence of entering 
tributaries is noteworthy; the small streams on the flood 
plain follow its slope, and hence run obHquely away from the 
main river; the St. Francis on the west is taken in above 
Helena when the river swings over near the western bluffs ; 
the Yazoo on the east is similarly taken in above Vicksburg. 
The dikes or '' levees," sometimes near the river bank, some- 
times half a mile or more away, have greatly restricted 
the spread of floods, but the levee system is not yet complete 
enough to prevent all floods; in 1897, when the levees were 



I40 DAILY ITINERARY OF THE EXCURSION 

less extended than now, 13,000 square miles, or about two 
fifths of the entire flood plain, were overflowed, and damage was 
done to the extent of $15,000,000. 

From Helena, we ferry across to Trotters point on the east 
bank, and there find our train, which then carries us eastward 
across the whole breadth of the flood plain, there known as the 
Yazoo basin. A large part of the plain is forested ; the prod- 
uct of lumber from this district has greatly increased in recent 
years. Near Greenwood, in the early evening, we leave the 
flood plain for the upland of the coastal plain, across which we 
continue our eastward route through the night. 

Fiftieth Day, Thursday, October 10 
BIRMINGHAM, ALA., TO CHATTANOOGA, TENN. 

We cross in the early morning the maturely dissected Appa- 
lachian plateau near its southern disappearance under the over- 
lapping Gulf coastal plain. The valleys of the larger rivers have 
a meandering habit ; they have southward discharge to the 
Gulf of Mexico ; our route is eastward, hence we frequently 
pass over cols from valley to valley. Suddenly the strata, 
heretofore horizontal, turn upwards, and we pass from the 
plateau to the folded Appalachian belt, with well-defined north- 
east-southwest trend in its subsequent ridges and valleys. 

In an open valley, close to the border of the plateau which 
supplies coal and in the folded belt which supplies iron ore, lies 
the active city of Birmingham, noted for its iron furnaces; here 
we stop for a few morning hours. About noon we take train 
again, and follow the valleys of the folded belt northeastward, 
crossing the northwestern corner of Georgia on the way to Chat- 
tanooga, just across the southern border of Tennessee. The 
leading characteristic of all this distance is the systematic align- 



CHATTANOOGA, TENN., PAST ASHEVILLE, N.C. 141 

ment of the ridges which follow the resistant strata, and the 
perfect adjustment of the valleys to the belts of weak strata. 
The contrast between the map of the Springville quad- 
rangle, surveyed in 1887 with 100-foot contours, and the Fort 
Payne sheet, surveyed ten years later with 50-foot contours, 
illustrates the great improvement in our newer topographical 
sheets. About midway, a broad synclinal mass, known as 
Lookout mountain, occupies part of the folded belt ; it is 
bordered on the west by a long anticlinal valley; west of 
that is a still broader mass, known as Raccoon mountain in 
its southwestern part, and as Walden ridge in its northeastern 
part , it is separated from the main body of the plateau 
on the northwest by the long, narrow Sequatchie valley, of 
anticHnal structure and remarkably straight course. Lookout 
mountain terminates in a point to the northeast, because its 
synclinal axis rises in that direction; at its foot on the Tennessee 
river lies Chattanooga, where we arrive in the late afternoon 
and spend the night. 

Fifty-first Day, Friday, October 11 
CHATTANOOGA, TENN., PAST ASHEVILLE, N.C. 

We ascend the northern synclinal point of Lookout mountain 
in the early morning; it was the site of a battle in the War of 
the Rebellion, fifty years ago ; the Great Appalachian valley 
lies southeast of us ; it is interrupted by low ridges ; beyond 
it rise the subdued mountains of the older Appalachian belt in 
northern Georgia. The Tennessee river comes toward us from 
the northeast, and after describing a fine meander, known as 
Moccasin bend, at the foot of the mountain, it turns northwest 
and enters a meandering transverse gorge, by which it passes 
through the next broad synclinal mass, separating the part known 



142 DAILY ITINERARY OF THE EXCURSION 

as Walden ridge from that known as Raccoon mountain ; thus 
the river reaches Sequatchie valley, along which it flows again 
to the southwest, until another abrupt turn to the northwest 
takes it into the plateau, which it crosses to the Ohio and Mis- 
sissippi. The origin of this river course has excited much dis- 
cussion. 

After descending from Lookout mountain, our train carries 
us several hours northeastward through that part of the Great 
Appalachian valley, known as the Valley of East Tennessee. 
The Appalachian trend of many low ridges is always noticeable, 
but in the broader spaces between them, the uplands are often 
dissected by insequent streams, while the larger rivers have 
pronouncedly meandering courses, as if they had learned to 
meander on broad, flat lowlands before the last uplift of the 
region, and had persisted in this habit after uplift ; thus carrying 
a senile behavior from the late stages of the preceding cycle into 
the early stages of the present cycle. We cross the meandering 
Tennessee at Loudon ; after passing Knoxville, where the Tennes- 
see is formed by the union of the French Broad and Holston 
rivers, we follow up the latter, and, on crossing its incised me- 
andering course, follow a broad valley to Morristown. Here we 
turn southeastward, and run across the grain of the country ; we 
cross the French Broad and follow up its left bank, thus reaching 
the outlying ridges that flank the older Appalachians, and then 
entering the mountainous belt in the district of its strongest 
development in North Carolina. The river gorge not infre- 
quently has precipitous sides beneath the graded slopes of the 
subdued hills and mountains, thus suggesting that an early stage 
of the present cycle follows a more advanced stage of the preced- 
ing cycle. This suggestion is soon confirmed, for after crossing 
to the right bank at Hot Springs, we enter the Asheville basin, 
an open space within the mountains ; here the hills and uplands 



CHATTANOOGA, TENN., PAST ASHEVILLE, N.C. 143 

have a nearly equal height, independent of rock structure; 
but the river is in a narrow valley below the upland level. 
The basin is presumably composed of weaker rocks than 
the surrounding mountains. The river is crossed twice again, 
the second time at Asheville, a noted mountain resort, where 
we stop for a noon visit. 

In the afternoon we resume our journey, turning eastward 
up the Swannanoa; its gorge decreases in depth, and the stream 
is soon seen flowing in the broad-floored valley of the earlier 
cycle, not yet trenched in this headwater district. Mt. Mitchell, 
67 1 1 feet, the highest of the Appalachians,, rises about ten miles 
north of our route, but it is hidden by lower summits. At 
Swannanoa gap (2522 feet), we begin a rapid and circuitous 
descent, passing from Mississippi to Atlantic drainage ; the 
valley of the Catawba, into which we run down, has hereabouts 
an altitude of 1500 feet. The deeply incised headwater valleys 
of this and other Atlantic rivers are seen to dissect a scarp of 
strong rehef, when viewed from farther down the main valley 
floors, and this scarp was nam.ed the Blue ridge by those who 
approached it from the southeast ; but from the other side it 
presents no well-defined relief, as its highland crest is overlooked 
by the mountains which rise still liigher. 

We follow the Catawba through an open country, with spurs 
of the Blue ridge on the northwest, and isolated mountain 
groups on the southeast ; the river is incised beneath the up- 
land level upon wliich the railroad is laid after we pass Mor- 
gan ton; this is the begining of the piedmont belt, an important 
feature of the older Appalachians in the Southern States ; it 
is an uplifted and dissected peneplain; the mountains that rise 
above it are monadnocks which still survive from the former 
cycle. We follow the piedmont belt northeastward through the 
night. 



144 



DAILY ITINERARY OF THE EXCURSION 



Fifty-second Day, Saturday, October 12 
LYNCHBURG, VA., TO WASHINGTON, D.C. 

The morning finds us still on the piedmont belt ; we cross the 
James river at Lynchburg, its valley being moderately incised be- 
neath the uplands. We continue northeastward, and approach 
outliers of the Blue ridge highland, among wliich we continue 
to Charlottesville, where we stop over noon to visit the Univer- 
sity of Virginia. In the afternoon we go on northeastward, 
soon leaving the higher hills and passing insensibly from the 
crystalline rocks of the piedmont belt to the nearly horizontal 
strata of the Atlantic coastal plain ; a single peneplain truncated 
both these structures, and the peneplain is now uplifted and 
submaturely or maturely dissected. We cross the Potomac, 
here broadened by slight drowning, and enter Washington, 
where we spend four days, October 13 to 16. 

Final Days, Sunday to Friday, October 13 to 18 
IN WASHINGTON AND NEW YORK 

During our stay in Washington we shall visit a number of 
governmental bureaus, the work of which bears more or less 
directly on geography ; and we shall make an excursion to the 
Falls of the Potomac at the head of a gorge, where the river 
passes from the resistant crystalline rocks of the piedmont 
belt to the weaker strata of the coastal plain. 

In the evening of Wednesday, October 16, we leave Washing- 
ton for New York, where two days will be devoted to meetings, 
and on Friday evening, October 18, the Excursion will disband. 



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